Technology Day 2008 - "Out of This World”
MODERATOR: Welcome to Technology Day 2008 edition. And I'd also like to welcome all the folks watching on the web. Increasingly, we're able to offer this program not only here in Kresge, but to the MIT community around the world. So welcome to all of you. Technology Day is the annual symposium that is organized by an alumni committee for your intellectual pleasure. In between all of the parties that you have during Reunion Week, we know you like to have a few moments of a little bit of hard thinking and also a chance to see some of the exciting work that's going on with today's faculty and students. The Technology Day Committee, if you would stand, I'd like to thank you for your work this year.
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And on behalf of the committee, I have to thank Lou Alexander, who is on the staff of the MIT Alumni Association. He runs this committee and makes our job extremely easy. And he is also responsible for the wonderful video that we had running, both here and on the web, as the introduction to the program. So Lou thank you to you for all the hard work you do on behalf of this event.
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Now, I'd like to say everyone, cell phones. Pagers, noisemakers, turn them off or down. That's always the first announcement. Thank you very much. And our program today, our theme is called Out of This World. And humankind has always had an interest in the heavens and the world outside of Earth. And today our first two speakers are going to help us understand that world.
Max Tegmark is going to talk about cosmology and our current understanding of our place in space. And then Professor Dava Newman is going to talk about humans in space and human exploration of space. And then our final speaker, Cynthia Breazeal is going to bring us back to Earth and introduce us a little bit to the parallel world of robots. So we have a very exciting program.
And I'm sure each of these speakers could talk all day, but we're going to try to limit them to about 35 minutes, so we have some time for questions. And this year, we're going to go back to the old-fashioned method of collecting questions on index cards. Those of you who have been to Tech Day in the past or other events with MIT alums know that there is a bad habit of asking questions, turning into long pontificating speeches, where it's hard to figure out where the question actually is.
So this, year the ushers, about five minutes before the scheduled end of the speakers' presentations, the ushers will quietly walk through the aisles and collect cards. So write your questions as you think them, pass them to the edges. And that will make it easier for the ushers to collect them. And then during the Q&A time, we'll also, if you have questions on cards, the ushers will come and get them. We'll do a little bit of vetting and organizing of the questions and do a little structured Q&A that way.
Let's see. So with that, I think that's the end of the preliminaries. And it's my great pleasure to introduce Beth Garvin, currently the executive vice president and CEO of the MIT Alumni Association, but soon to be former CEO. She has just accepted a job at Brown and will be heading-- oh, RISD, ooh, sorry, RISD, that other school in Providence. And we're very excited for her, although very sad to see her leave the MIT Alumni Association. So Beth.
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GARVIN: Well, good morning. It is always my pleasure at this event to officially welcome you back to MIT on behalf of the Alumni Association. As we prepare for reunions, I always remind the staff that there is a bit of a shock sometimes for alumni as they return. The campus is quite different, for many of you, since your last visit.
And on the staff, we tend to think about the brand-new buildings, the Stata Center or Simmons Hall or the construction that's going on seemingly endlessly on Cambridge streets. But I've had a couple instances this week that remind me that those aren't necessarily the questions we're going to get. I had one very frustrated alumnus asking me earlier this week where McCormick Hall was, because, you know, that wasn't built when we were here. I said, oh, yeah, yeah, yeah. So we kind of traced Ashdown as being a landmark and figured out how to get there.
Last night someone asked me, just remind me, which one is Kresge? And we forget. Change is such a constant here, that we forget how much this place has evolved. And it reminds me of the collective wisdom of the people in this room. You are the people who have seen MIT evolve not just physically, but in the curriculum, in the leadership, in the face of our students today.
And it's wonderful to have a chance to have all of you back here and sharing some of that wisdom and knowledge and experience with us. At the very same time, we see our class of 2008 graduate. It's a wonderful opportunity to bring MIT together. And we're very grateful to have you here, spending some of your time with us.
The community of alumni has become increasingly connected over the years. Some of that is due to the wonderful power of our online tools. But a lot of it is just because of the personal connections that we've been able to help facilitate.
I wanted to just mention, in the couple of minutes I have today, about one real transformational change I've had the privilege to watch over the last 10 years or so in the Alumni Association. We were trying, with the encouragement and pushing of the Alumni Association Board of Directors, to find a way for alumni to play a more meaningful role at MIT. Obviously, the role as donors is incredibly meaningful and critical to MIT support. But we wanted to find more ways for the alumni to be mentors, advisors, teachers, and learners, and friends.
In the past couple years, it has been delightful to watch how some of these new roles have emerged and become a really powerful part of the MIT alumni community. There are lots of examples I could share about how this engagement has grown. But I want to just mention one, because it really came home to me vividly yesterday.
The externship program that the Alumni Association sponsors during IAP gives students a chance to go out into the work world with alumni. These externships might be one week. They might be three weeks. Some are paid. Some are unpaid.
They are in large corporations. You might be working on a trading floor at a major investment firm. You might be working in a startup. You might be shadowing a doctor.
And they have become very meaningful to the students. Students tell us how much this influences their careers and their career choices, sometimes learning they really don't want to go into the profession they thought they wanted to go into. But that's a good thing to learn when you're a sophomore rather than after you graduate.
And alumni tell us how much they enjoy having the best and the brightest in their firms, working with them, getting a chance to see what MIT is really like today. And they like the ability to recruit those students for summer jobs and possible placement after graduation too. So it's really a win-win for everybody.
This year, and this is where it came home to me yesterday, the class of 2008 set a wonderful new record in senior gift participation. I don't want to share that with you today. That's their story for the Tech Day lunch. But from my perspective, it was just as gratifying to see what they chose to support at MIT.
Often the senior gift wants to leave something tangible, a clock, a map, a fountain in Killian Court. They all want a fountain in Killian Court. And we sort of have to guide them to something that might be sustainable, lasting. And this year, on their own, the students came up with the idea of creating a fund to support students during IEP external ships for those externships that aren't paid.
They wanted to make sure that students had the opportunity to go do the things they really wanted to do, to connect with alumni, to get an experience outside the classroom that was meaningful. And to me, that just brings this community together in a new and wonderful way and just shows the power of all of you in this room to influence the future. So I could talk for hours about wonderful examples.
But you're here to hear from the amazing faculty. I'm here to welcome our amazing alumni. Enjoy the day. And I look forward to talking to all of you. Thanks very much.
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MODERATOR: Thank you, Beth. And we wish you all the best as you transition to RISD. Now it's my great privilege to introduce Susan Hockfield, the 16th president of MIT. Susan started her career as a neurobiologist, but her leadership skills were recognized early, and she moved up through the ranks of departmental and then academic and then university administration.
Prior to coming to MIT, she was dean of the graduate school at Yale and then provost. We're very happy to have her here and are excited about the way she's leading MIT in the 21st century. She's got some remarks for you as well. And without further ado, I give you Susan Hockfield.
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HOCKFIELD: Good morning. Welcome to Tech Day. I was reflecting. This is my fourth Reunion Weekend, and it's an acquired taste.
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Actually, the first two years, when I staggered through this incredible compendium of events, all I could think of was, who the heck designed this? Had to have been an engineer.
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But I found myself, starting about the beginning of May, actually looking forward to this firehose. And it is so wonderful and so MIT to combine commencement with reunions and bringing everyone to campus and, as Beth has so beautifully talked about, all of these connections that know lie at the heart of MIT. So welcome back, everyone. It's wonderful to see you all this morning.
I'm going to try to restrain myself. But those of you who've heard me speak before, you know it's difficult. What I want to do is preserve about 10 minutes of the time I have with you this morning for questions. And so I hope you will write questions on those index cards. Because as I often say, I'm far more interested in addressing the questions you actually have than the ones I imagine you might have.
So the first part will be my addressing the questions I think you might have. But then I want to allow enough time. So I'm going to be very brief in giving just have an overview of where MIT is and where we are this year. It's been a spectacular year on campus, lots of successes, lots of advances.
Let me just tell you that the three faculty you're going to hear from today-- I could say this at any Tech Day but-- they are the superstars. I often talk about MIT's magic of working all along the continuum from the most abstract theories to the most advanced applications. And the three faculty today really show you that continuum in incredibly vibrant ways.
Dava Newman, who you'll hear from, her bio suit, which is over there, I think there's a version that is on view at the Metropolitan Museum of Art. It will be there until the end of August, just an example of how the news of what's coming out of MIT gets around the world. Max and Dava are both just back from the World Science Festival.
We have a Science Festival here. We actually have the first Science Festival in North America here. We started it last year. But we call it the Cambridge Science Festival. They did one in New York last week, week before last. And they called it the World Science Festival. Cambridge needs do a better job of imagining ourselves as the center of the universe. We'll call it the Galactic Science Festival.
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And the news of MIT, I'm just delighted. I see references to stories about it everywhere. Let me just tell you about four fabulous mentions of MIT in the last year. There was an article that appeared in The New York Times in the International Herald Tribune asking a question of, in economics, who are the John Maynard Keynes and Milton Friedman's of today?
And the writer took the perspective that a lot of economics has gone very small. Some of it gets be kind of flashy news, like about gambling or shopping. But the writer was reflecting on where are the people who are really changing the view of the world, the way Friedman and Keynes did?
And so he did a survey of leading economists. And then he writes, "the runaway winner was a small group of economists who work at the Jameel Poverty Action Lab at the Massachusetts Institute of Technology, led by Esther Duflo and Abhijit Banerjee. Not bad. Not bad that Esther and Abhijit are being put in the category of Keynes and Friedman. And actually, I think the work they're doing actually is equivalent.
They are operating from a simple but quite radical idea that they could be as systematic in testing methods that are designed to alleviate poverty, as we are for drug trials. So they look for the application of these huge funds in a controlled way so that they can actually measure the outcome. This is an idea that is really catching on. The Jameel Poverty Action Lab is flourishing, has grown enormously over the last several years.
Then Open Courseware, I always get a question about Open Courseware when I talk to alumni. It makes me feel very proud of MIT. It's being noticed by other people, too. Bill Gates had a column in Fortune, where he talked about the challenge of global education.
I was in India in November, and the challenge of building capacity in education is so pressed there and in other parts of the world. And he cites as the model solution, Open Courseware, where we now have 1,800, almost every one of our courses online. We get emails from people around the world for whom this has really changed their lives. Now, I have to point out that as much as Bill Gates might love Open Courseware, he has not gone the next step, which is to supporting Open Courseware.
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I've got to get a meeting with him in the coming year. Tom Friedman was on campus for the celebration of reaching our 800 courses on Open Courseware in November. And he is a marvelously curious intellect. And so he roamed all over campus while he was here to give the keynote for the Open Courseware celebration. And he found his way to the Vehicle Design Summit. Some of you may have heard this.
This was the brainchild of two women engineering students a couple of years ago. They had the idea of gathering the students who previously had competed in the solar car race to come together and collaborate, building a vehicle that will get 200 miles per gallon. This has now become an international phenomenon. He titled the his op ed on this particular piece from their tag line, "We Are the People We've Been Waiting For."
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I look at the students today, and I just say, you sure are. They are the people that we've been waiting for. And they are not the kind of people that we were in college. You all know what we were doing when we were in college. It was not rolling up our sleeves and getting to work. But they are certainly rolling up their sleeves and getting to work.
And then most recently, CBS Evening News is doing a whole series on cancer, I would think mostly precipitated by Senator Kennedy's terrible diagnosis with brain cancer. And so they are looking at the frontier of cancer research. And they have featured cancer research going on here from Bob Langer, Sangeeta, Bhatia and Phil Sharpe.
Now, these last two things I talk about, I mentioned, tie into two of the big campus initiatives. And I say the two big campus initiatives. There are hundreds of brilliant and wonderful and world-changing things going on on campus. But these two large initiatives have really taken form and gained traction in the last year. So let me give you a short update on each of them.
The Energy Initiative was officially launched only a year and a half ago. It is raging through campus like some kind of storm. About 15% of our faculty have written white papers or participated in some way in the Energy Initiative.
The Student Energy Club has 750 members, mostly graduate students. When I asked the co-presidents what this club was about, thinking of a club in a sense is something you do as your hobby, they reminded me rapidly and severely that the reason they're in the club is they're going to be working in the field. So MIT is producing the future energy pioneers, the energy technologists, scientists, policymakers at a rate that is simply staggering and really quite wonderful.
The initiative, if I can just kind of put it in its very short form, because it reaches across campus, there are many things we're working on, not on everything. But the way we collect up the ideas is in two different pieces. We all long for the transformation, the new technologies that will power the world and get us off fossil fuels. And we're very interested in those.
But those are not going to be scaled up and ready to use for quite a number of years. So the first part of the Energy Initiative is focusing on innovations. What are the changes that we can look for this year, next year, five years from now that will improve our current technologies? So there's a lot of work in clean coal. There's a lot of work improving nuclear power, a lot of work increasing the efficiency of how we use power today.
I like to think of efficiency as the fifth fuel. So after oil, gas, coal, and nuclear, conservation is going to be as important in meeting the immediate challenges, as any of these technologies. The second piece of the initiative is about the transformations. And boy, do we have a huge group of people working on exciting transformations, solar, wind, waves, tide, geothermal, biomass, and biofuels, really doing cutting-edge breakthrough work.
Now, this is a bottoms-up activity. It's not an idea I had. It's an idea the faculty, students, staff, and all of you also had, the alumni. And so we're allowing it to evolve. And what's evolved over the last, I would say, probably four months, what's emerged as the centerpiece of our Energy Initiative is solar.
And I am delighted about it because I personally view solar as the ultimate technology. When we can get to all solar, to all electric, we will be off fossil fuels in an important way. And some people who are not yet converts say, well, why would you do solar? And it's a little bit like Willie Sutton and the banks, where's the money?
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Where is the energy? It's in the sun. An hour of sunlight falling on the earth provides enough energy to power the entire earth for a year. We have got to make better use of this particular energy source than simply heating up asphalt.
The other initiative that I want to mention is just one piece of where engineering, the life sciences are coming together in just amazing and powerful ways. This will be a source of changes that will transform our lives, the way computers and the information technologies have transformed our lives in the 20th century. One piece of that is our new Cancer Institute. It's led by Tyler Jacks.
And what it brings together are about the dozen faculty in our Center for Cancer Research that have been bringing forward the basic science behind cancer since 1974, bringing those faculty together, with about a dozen fabulous engineers who are thinking about cancer. Because we believe that the next most important insights about how to diagnose, treat, and prevent cancer are going to come out of this fantastic fusion of engineering with the life sciences. I'm enormously optimistic about the approach.
And I have to tell you, this is not theoretical. It's real. And the example I give, although it's a kind of a poor example against the complexity of cancer, is heart disease. The NIH invested something on the order of $4 a year per person in America over 30 years in cardiac research.
That's resulted in a decrease in death from heart disease by over half. What were those advances that permitted that kind of decrease? Well, they came out of both biology and technology, drugs-- how many of you have heard of Lipitor-- and devices, drug-eluting stents. The pioneer for drug-eluting stents is, of course, Bob Langer, who is a critical member of our Cancer Initiative. So bringing together these two different perspectives on what a problem is and how you solve it will be very powerful in addressing cancer.
The Koch Institute for Cancer Research right now is a big hole in the ground between the Ray and Maria Stata Center and the Koch Biology Building. We hope to open that building in 2010. Now, both of these initiatives are up and running, the Energy Initiative, in its first phase, focused on industry support, industry partnerships. That's gone very well.
We've raised over $160 million in commitments for the Energy Initiative. We have money for about 100, I think over 100 student Fellows, graduate students, who will be working in energy. But for both of these initiatives, the next phase is really going to turn to private philanthropy.
As you all know, I need not remind you that federal support of research is not what it should be. In the mid-1960s, this enormous fuel for America's innovation economy was funding research in America about 2% of GDP. This year it's less than 1% of GDP. So we are turning to other sources for support of the kind of work that we believe is critical for America to have our leadership. Some of that's industry support. Some of it is private philanthropy.
I will make only one comment about MIT'S budget. Some of you are interested in our finances. I saw Terry Stone, our new executive vice president, in the audience. She, along with the Provost Rafael Reif, Israel Ruiz, our new vice president for finance, have done a spectacular job building a new financial framework for MIT.
The budget that we've submitted for FY '09, the first time in many years, is balanced. We have moved to a smoothing rule for use of our endowment that will reduce the volatility of endowment pay out. The endowment now provides about 20% of our operating costs. And half of those costs are people. And as all of you know who run businesses, people are hard to move as the economic volatility changes, particularly here at MIT, where our faculty and our students are really the core of our enterprise.
We are in a very positive track to think now very productively about our future. We have new deans in many of the schools. I would say the oldest dean, longest-standing dean is Del Santos, who was here just less than a year when I arrived. These new deans over this year have gained traction in an incredible way. They have the confidence of their faculty. But I would say more extraordinarily, because they have all essentially started together, they are collaborating in ways that really haven't been seen before, bringing together the expertise from MIT Sloan, with the School of Architecture, with the Schools of Engineering and Science so that we can, in a very serious, very unique way, I believe, address problems as large as energy and the environment, as large as world poverty, as large as making a change in health care for cancer and other diseases.
Let me just wrap up with a couple of very, very positive indicators. This admission seasons was as chaotic as any that anyone has ever seen. Those of you who follow this closely, probably few of you follow it as closely as I do, in the fall, Harvard, Princeton, and University of Virginia all stopped doing action early admissions early of any sort, threw a huge amount of uncertainty into our admissions.
And then you, I'm certain, have been reading about the change in financial aid policies at Harvard and Yale and Stanford. And Princeton actually was there several years before those schools. So we did not know what was going to happen with admissions.
I have very good news to report. The applications for MIT were up 8% again. This is three years straight of 8% or greater growth in applications. This, of course, makes us feel good that so many brilliant young people want to come to MIT. But I think it's an important message around the nation.
We accepted just less than 12% of the applications, which means these students are going to go someplace else. Most of them are going to go someplace else. But it means the students in America and around the world are increasingly turning to science, technology, and a science-and-technology-based way of thinking about the humanities, arts, and social sciences that MIT represents. This is good news for the country.
We admitted, as I said, just less than 12% And our yield on those students was just over 66%. This is wonderful in the face of all of this turmoil in the admissions universe. This was not our top year, but the third-best year for yield at MIT.
Let me just talk a little bit about our financial aid policies. For 40 years, MIT has been practicing need-blind admissions, absolutely need blind. We also provide aid that is entirely need based. We don't provide any kind of merit-based aid. Many of these schools, in fact, I would argue that most schools do provide merit aid, and we don't do that.
We're also committed to meeting the full need of all of our admitted students. This has been a more aggressive financial aid policy than anyone would know. Up until this year, MIT was spending more financially dollars per enrolled student than any of our peer institutions. We certainly were spending more financial aid per endowment dollar than any of our peer institutions.
So we have really been out there ahead. This policy has been fantastic. The year's-- the freshman class that will come next year, 18% of those students will be the first in their families to go to college. The students here on campus, 30% of our students on campus come from families with annual incomes of less than $75,000 a year. This year we committed to meeting the full tuition needs of these families. Fully 17% of our students come from families with incomes of less than $45,000.
MIT, as you've heard me say before, is a place where the American dream comes true. You all have told me your stories of how getting financial aid allows you to come to MIT. And coming to MIT allowed you to change the world. Well, we are staying true to those policies, and it is clear from our admissions results that MIT remains, I would say, it continues to grow as an attractive place for the most brilliant, the most ambitious people in the world to come, the people who really do want to change the world.
We have had a great fundraising year. Thank you all for participating in the alumni fund. We have set a new record there. We set a new record in resource development. And what I can say about this is that what we do at MIT clearly resonates with alumni and with others.
I could talk about some of the startling achievements of our faculty. But I'm going to let the faculty talk about them themselves. Well, our three faculty will talk to you about it.
The last thing I'll say, I'm going to reveal the secret of the senior gift, which Beth very decorously said would wait for lunch. Some of you aren't going to be at lunch. But I would say, for me, the most important measure of our success is the seniors.
Having been given a chance to say thank you, my time at MIT meant a great deal to me, the senior gift this year has blown away all previous records. The year I arrived, four years ago, when I stood at this podium, I didn't talk about the senior gift because the participation that year was 27%. And I could not say that without hanging my head in some embarrassment, thinking, do only 27% of our students think that this was a valuable experience for them?
So Beth and I put our heads together. And I challenged Beth to challenge the students to say, please tell us that this was important to you. This year's senior gift, when I last checked, was 65% participation. Hurrah, for the class of 2008!
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And I would say hurrah for the Alumni Association. I am heartbroken that Beth will be leaving us. She has led the association in extraordinary ways. She is going on to a new challenge, which, I have to say, I can understand how RISD calls on a spirit who has been motivated by MIT, how the spirit of RISD would motivate her further.
Let me stop there. And if I've left any time, perhaps we can get some questions in. Thank you all very much for coming back to campus and joining us for Tech Day.
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MODERATOR: Well, the index card system is working. We have a few really good questions for President Hockfield. The first is, Susan, what has surprised you the most about your job here at MIT?
HOCKFIELD: Oh, what surprised me the most-- it's a great question. People ask it all the time. So I should have a ready answer. I will tell you, quite frankly, the thing that surprised me the most-- you all know I was at a pretty good school before I came to MIT. And I had a pretty good job at that pretty good school. And other schools had tried to persuade me that it would be more exciting to go to their school and lead them. And I said, you know, I really don't think it can be more interesting to go to your lovely school.
But when MIT came calling, obviously, it was a compelling, I would say an irresistible call to service to come to MIT. And I came here because I knew that it's a great place. It's the best science-and-technology-based university in the world.
The thing that surprised me most, MIT is far better, far stronger, far warmer, far more interesting than anyone on the outside knows. This place continues to take my breath away. Every time I talk to faculty-- you'll have this experience this morning-- I find myself in a future I had not yet imagined. At my previous very fine school, that happens from time to time, but not with the kind of dependable regularity that happens to me here at MIT.
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MODERATOR: And next question is, what do you see as the key challenges-- and the questioners suggests that you propose your top five-- that face MIT in the coming years?
HOCKFIELD: Good. Is this mic-- great. You can keep the podium. I'll walk around with this in my hand.
MODERATOR: Perfect.
HOCKFIELD: The top five challenges-- if I do the top five challenges, we won't have any more questions.
[LAUGHTER]
MODERATOR: So pick your top two.
HOCKFIELD: Let me pick a couple. The first is a challenge I mentioned, which is support for the enterprise we're engaged in. This is a very serious challenge. I mentioned the problem about federal research funding. This is an important challenge not just for my team, but for the nation.
We really have to get our heads around the fact that these are investments. They're not expenditures. I gave you some numbers about research in heart disease that has really transformed-- transformed-- saved lives. These are investments.
I can give you the same kind of numbers for the battle on AIDS, which in the beginning of the '80s, it looked like-- by the mid-'80s, it looked like every hospital bed everywhere in America was going to have an AIDS patient in it. We have turned AIDS from a death sentence to a chronic, manageable disease through investments-- through investments.
The return on the investments to come up with a treatment for AIDS has been 140 times. So as a nation, we really have to get ourself oriented. So that impacts MIT and MIT's team's commitment to helping build life-changing technologies.
But it's also true for education. No one could have escaped hearing about the battering, that I would say, that higher ed has gotten at the hands of Congress and now the media this year. This is ridiculous. The higher education system in America is the best in the world. We are the envy of the world.
And for Congress and other people to spend their time beating up these well-endowed institutions-- well endowed-- what do we do with those dollars? We turn them into these discoveries. We turn them into the inventors and the innovations of the future. So this is a very serious challenge for MIT and also for the country.
On the positive, side we have a fabulous challenge, which is only ours to address. And this is the challenge of problems that reach far across departments and schools, reach between institutions, reach between the academy and industry. And so a really important challenge for us is building the kinds of interconnections that allow our spectacular faculty and students to really get their hands around the problems of today. Now, this is a problem I think MIT is positioned to address better than just about any university in the world. And so I embrace this challenge in a very active way, as do our faculty and students.
MODERATOR: Great. I think we have time for one last question. And actually it addresses a couple of questions that came through. One is, MIT attracts elite young people for its science and engineering program. But the need for engineers and scientists is great. And another question says, is MIT doing anything toward changing current attitudes of the US public towards science?
Now, I know that K-through-12 education is one of your big concerns. And also, I know I've been reading your op-eds in The Boston Globe. But maybe this audience would like to hear a little bit about those initiatives and how you're trying to address these concerns that are raised by these questions.
HOCKFIELD: Yeah. So this is something I committed myself to, the Institute to when I started. And I will share with you a story. When I first met with the search committee, it was this period of kind of getting to know you.
And the search committees always ask a question-- and I'm guilty of the same thing when I've been on a search committee-- what should MIT do? And I looked around at this group who knew infinitely more about MIT than I do. I said, how would I know what MIT should do? Would you please tell me what MIT should do?
But then I made an appeal. I said whether the next president is me or anyone else, it's very important that MIT share the news of what we do far more broadly and far more powerfully, and I have. And Kim has mentioned a couple of the efforts to share the news about MIT. I hope you have noticed that you-- I hope you really are noticing that mentions of MIT happen more frequently in the newspapers and the media that you read.
I did a piece on Charlie Rose beginning of February to help get the story out, I had a series of op-eds in The Globe. But it's not just me. Our faculty are traveling around the world. Our alumni sit all over the world and are the information army. It's very important that what we do and how we do it at MIT is a story that gets out.
I talk about MIT being a more powerful beacon for inspiration around these issues of science and technology, science and engineering. And I talk about the visual piece of this, which is lighting the dome a year ago, moving the MIT museum to the first floor. So anyone who travels up or down Massachusetts Avenue can get a peek at the fabulous innovations that are going on here.
Open Courseware is another vehicle that we're using to inspire the world or give access to science and engineering that people wouldn't normally have. At our event in November, when we announced our goal of having our 1,800 courses online, we also celebrated the opening of a new portal for Open Courseware. It's called Highlights for High School.
One of the things that we discovered among the users of Open Courseware was that a lot of high school students and high school teachers are using Open Courseware. Any of you who have been on the site know that it's not such an easy site to navigate. And so we imagined we could create a portal that would make it more accessible for these high school students and teachers.
So we opened a portal, Highlights for High School. It's really a pilot phase. It's going very well. Any of you who's interested in this kind of outreach should go on the site. It is just a very exciting site. And in true MIT fashion, what I imagined it would look like is dwarfed by what it actually does look like. So this is one way of getting the information out.
We are working-- I've got a team of people working on how to increase the visibility for MIT. And believe me, it's not about it being good for MIT, although I believe it will be good for MIT. It's about a stronger, more powerful way for MIT to serve the nation and the world. So this continues to be a work in progress.
I would say you are the best measures of whether this is happening. So I hope in another year or two years or five years, when you're back, you will be able to say with confidence, sure enough, I'm hearing a lot more about MIT in the world. And more than that, is that kids in the high schools in my town, my city, are asking about, how can I go to MIT? How can I pursue science and engineering so that I can help invent the future for America and the world?
With that, thank you all for coming to Tech Day. It is great to have you back on campus. Share the world about MIT where you come from.
[APPLAUSE]
MODERATOR: Thanks so much to Susan Hockfield for giving us that brief insight into what's happening at MIT team today. And now, while he gets his computer set up and gets ready to go, it's my pleasure to introduce Max Tegmark. Max is an associate professor in the physics department here. And his specialty is something I have to read, precision cosmology.
And so I hope that in the next 25 minutes or so, we'll gain an understanding together of what that is. So thank you, Max. Welcome.
TEGMARK: Thank you.
MODERATOR: Welcome.
TEGMARK: It's a great pleasure to be here.
[APPLAUSE]
And it's a great pleasure to get to work on cosmology here at MIT because there are just so many wonderful people to work with. We're extremely enthusiastic about this subject. Precision cosmology, as you mentioned, that sounded kind of like a joke.
[LAUGHTER]
It's not too long ago when people have been arguing for ages about the factor of 10 in some measurement. And there's a factor of 10 in the exponent, right?
[LAUGHTER]
And as I hope to share with you today, that has really changed. And it's changed because of tech, which is the theme of our day today. And it's not just I who feels excited about cosmology. Even my curmudgeon Swedish countrymen on the Nobel Committee have realized it's exciting and decided to give a Nobel Prize to the field recently, John Mather and George Smoot.
And of course, where did he get his PhD, any guesses? And we'll come back to what they discovered shortly. But first what I would like to do is completely turn off these flood lights here up in front and get it really, really nice and dark and take you on a little journey to remind ourselves of our place in space.
Let's turn the lights off completely. Thank you. So what's this?
AUDIENCE: Kresge.
TEGMARK: Very good, the Kresge Auditorium. So let's go for a little ride. I promise we'll come back.
[LAUGHTER]
So as we start zooming out, we need to make a slight change of equipment to be able to go a little bit further. And just to set the scales here, in our solar system, as you all know, it takes light about eight minutes to get from the orbit of the Earth, from the sun out to Earth's orbit. So we see the sun not the way it is right now, but the way it was eight minutes ago.
And nonetheless, our solar system is puny compared to the distances to the nearby stars. What you're seeing here is not a computer simulation, but a real three-dimensional map of the stars in our neighborhood, painstakingly built up by astronomers across the world. And the typical stars you'll see here in Cambridge on a clear night are hundreds of light years away, which means that if someone out there is looking at us, they won't see us. They might see the Boston Tea Party.
[LAUGHTER]
And this, as well, is what we casually call our solar neighborhood in my field. It is just a small part of this beautiful agglomeration of hundreds of billions of stars we know as our Milky Way galaxy. We live about here, about 100,000 light years from side to side, beautiful pizza shape, with a big bulge in the middle and this familiar spiral structure seen from the top.
Now, for me, it's quite remarkable to think that when my grandma went on her first date, this was the universe, a little part of this galaxy. It wasn't until 1925 that the American astronomer Edwin Hubble showed that there were other galaxies. And now we're so spoiled, that with just a few clicks of my mouse, we can zoom out until our whole galaxy is just a little dot. And now all these other dots aren't stars anymore. They're other galaxies, with hundreds of millions of stars of their own.
And if we pretend for a moment that the speed of light is infinite, so I can drive as fast as I want, then let's take a little ride and check out our intergalactic neighborhood. Now we're hundreds of millions of light years away. So if you took a peek back from here, you wouldn't see the Boston Tea Party, you might see dinosaurs roaming around here.
And there are two things that really jump out at you. Again, first of all, this is not a computer simulation. This is a real three-dimensional map of our neighborhood. The two things that jump out at you are first, galaxies are kind of like MIT alumni. They like to hang out with others in groups, clusters, super clusters. And you see these giant filamentary structures here, basically because gravity is an attractive force and clumps stuff together.
And moreover, wherever you see lots of galaxies, we've since learned that there is also much more dark matter. So you're effectively seeing a dark matter map here illuminated by galaxies, much like when you're flying over Boston by night. You only see the city lights, which make up a small fraction of all the stuff. But from the contours, you can learn a lot more about what's really there.
The second thing which jumps out at me when I look at this is that by now, it's getting a little bit boring. It's kind of like you've been there, done that, more of the same. And we have a fancy geek word for that. We say that the universe is homogeneous and isotropic on large scales, which in plain English just means that on average, our universe seems to be kind of the same everywhere. It's only when you zoom out still more that you see that, in fact, it's a cube.
[LAUGHTER]
This is, of course, just a reiteration of Susan Hockfield's remark that we have plenty more to do in science. In this case, we want to map farther and go beyond where our funding ran out here.
[LAUGHTER]
So let me now share with you a little bit about a project that I have spent a lot of time working on with my colleagues. It's called the Sloan Digital Sky Survey. And it's the most ambitious project, to date, to map our universe in two and three dimensions. And let's turn off these spotlights again. You can keep it nice and light there in the back so you don't get too comfortable in your seats. But this is perfect.
Now, what I want to do is just show you our data. You recognize the Big Dipper here. And I'm going to just zoom in on [INAUDIBLE] sky map on a part right below the tail of the Big Dipper. These are just photos. I can zoom in like this anywhere in the sky. I encourage you, when you get back home, to go to Google Sky and fly around because they have our Sloan Digital Sky Survey data in there already, just to give you a sort of sense of what 10-to-the-power-8 objects really involve. It's a huge amount of information.
And then what we do with this is we have a-- of course, I can't give a grad student 10-to-the-eight objects and tell them to come back when they've looked at them all. So you feed them to your computer. And the computer selects out the most interesting ones. And then one goes back and measures distances to them.
And then we can go and build up these kind of three-dimensional sky maps that we flew around a minute ago. And let's start again at the Milky Way now and then start heading out. You can hear a narration here by my colleague Josh Freeman.
[VIDEO PLAYBACK]
- [INAUDIBLE] nearest galaxy mapped by the Sloan Digital Sky Survey. The Sloan Survey records the images of galaxies [INAUDIBLE] giant [INAUDIBLE], that later measures light from each galaxy in more detail using an instrument called a spectrograph. We are now tens of millions of light years from Earth. Galaxies come in a variety of shapes, sizes, and colors, from typical blue spiral galaxies, like our own Milky Way, to giant red elliptical or oval-shaped galaxies.
Now hundreds of millions of light years from Earth, we see that galaxies collect together in groups, ranging from a few galaxies to great clusters containing many hundreds of galaxies, to large web-like structures stretching across hundreds of millions of light years. The survey is being carried out in thin slices across the sky, like pieces of a watermelon. When completed, these slices will merge together to form a three-dimensional map of the universe.
Cosmologists believe that these large-scale structures evolved from small ripples in the fabric of space, generated a tiny fraction of a second after the Big Bang, about 14 billion years ago. Beyond the Sloan survey, we reach the cosmic microwave background radiation as mapped by NASA's WMAP satellite. This radiation gives us a picture of the universe when it was only 400,000 years old.
The colored patches show directions on the sky where the temperature is slightly hotter and cooler than average. By analyzing and comparing the data from these different kinds of surveys, cosmologists are closing in on a consistent picture of how the universe evolved from its earliest moments to the present day.
[END PLAYBACK]
TEGMARK: Now, wait a minute. Just when it all seemed like what we were doing was mapping space, we bump into this weird greenish sphere. What's that all about? And you heard my colleague Josh Freeman calling it the cosmic microwave background, which is what George Smooth and John Mather were awarded the Nobel Prize for taking pictures of.
So what on earth is this? Why does it look like we're surrounded by a giant sphere? We clearly need to get to the bottom of that. And to understand it, we must understand not only our place in space, but also our place in time.
Of course, since it takes time for light to travel, the farther way we look, the farther into the past we see. What you're looking at here is for-- raise your hand if you would classify yourself as a photography buff? All right. I am touched to see so many kindred souls here.
This is an extremely cool photo. Imagine being able to take a four-month exposure with your camera with a lens which has a 2-and-1/2 meter opening. You then have your telescope in space. So it's always pointing toward the same part of [INAUDIBLE]. Let's dim these front spots again. Otherwise they will miss the [INAUDIBLE] galaxies.
And moreover, because it's such an amazing photo, you can get amazing detail. The entire part of the sky you're seeing here is so small, that if you hold up your hand like this and imagine you're holding a pin in it, from here to here corresponds to the width of your pinhead, the width of a needle. It was taken with the Hubble Space Telescope.
And you see a lot of things here which happened 12, 13 billion years ago. So looking back from there, you wouldn't even see Earth, which only came on the scene 4 and 1/2 billion years ago. And from looking at different distances away from us, we've been able to put together a very quantitative picture of what our universe looked like at different times in the past.
I'm summarizing it all on this slide here. We know that everything that we can see, everything in the spherical region from which light has had time to get here so far it, was about 14 billion years ago, extremely hot and dense. We call this our Big Bang.
And since then, two basic processes have been taking place. All this stuff has been flying apart, expanding, which has caused it, of course, to become less dense and also less hot. And there's a second process as well. It's transformed from being very smooth, much like the air in this room, where the density varies from place to place only at part in 10 to the minus 5 because I'm talking, because of sound waves, if I'm about this loud-- was very similar in our cosmic past.
And then gravity amplified this and transitioned to smooth gas distribution, just a smooth hydrogen gas into clumpy and interesting hydrogen, which eventually turned into the galaxies, the planets, and MIT and all the other good stuff we have today. And you can see that illustrated schematically here. Again, by looking into the past with various techniques, we can map out more recent past, various galaxies, see back to a time before there were any galaxies, and thereby figuring out when galaxies started to form.
And then when we look still further back, we see this funky cosmic microwave background, which we need to explain and understand. And before that, my colleague Alan Guth here at MIT came up with the most popular explanation for what happened, called inflation. The theory is that if you just have a very tiny region of space containing a substance which won't dilute very much when it stretches out, then that tiny region of space will rapidly double and double and double its size and expand and become larger than everything we can see.
There are many different techniques which have burst on the scene, combining various technologies to let us peer into the past and get quantitative about this. So 30 years ago, cosmology was largely viewed as somewhere out there between philosophy and metaphysics. You could speculate over a bunch of beers about what happened, and then you can go home because there wasn't a lot else to do.
Whereas now we're treated to this wonderful data, given to us by space technology improvements, detector technology, and computer technology to make sense of it all, right? We've talked a lot already about galaxy surveys by flying around in our universe. Let me explain now what this microwave background is.
So when we look into the past, we're looking through all this black stuff in, which we, as kids, called empty space. But it's not empty. It's all full of hydrogen. And when you look farther back, this was denser and denser, hotter and hotter.
If you just heat up a bunch of hydrogen, eventually it gets so hot that it turns into a plasma. And the plasma is opaque, just like the wall there. So it looks to us like we're staring into an opaque plasma screen over on that side.
But of course, it's going to be the same whatever direction we look. So it's going to appear to us like we're inside of a plasma sphere. That doesn't mean we're in the center somehow of everything. It's more like when you're walking around in the fog, and you can only see 100 yards in each direction. You're going to be in the center of your own fog sphere, right? But so is everybody else. So don't get hubris from this.
[LAUGHTER]
Now, fortunately, technology has given us great maps of this plasma sphere. You can just photograph it. You need to do you'd have a microwave camera. And the first to see these patterns where the Nobel laureates I mentioned. These better pictures were taken by NASA's Wilkinson Microwave Anisotropy Probe Satellite, which has revolutionized the field.
Since we talked about money, I thought I would share with you what this cost. This amazing experiment, which has revolutionized our field, cost $0.40 per American.
[LAUGHTER]
There is a good investment if I've ever seen one. Now, let me summarize the storyline of how we got here in slightly more visual terms. So I talked about two processes, expansion and clustering. This is a supercomputer simulation performed by Ben Moore and his group, where you see both the expansion and the clustering.
And all he's done is he's put the laws of gravity into his computer. And rather uniform stuff flying apart. And you see eventually how you start getting very complicated and intricate clustering patterns here. My eyes get mostly drawn to the expansion part here at the expense of the clustering. So let me show you another version of this, where the expansion is just artificially taken out so you can see how gravity has the power to transform something rather uniform and boring to something really clumpy and interesting.
This is a few hundred million light years from side to side. And you'll recognize very similar patterns here predicted by pure theory in your computer to the galaxy distribution that we flew through, right? In fact, the individual blobs that we're seeing here are the scale of typical galaxies. So you can imagine that within each of them it might evolve a galaxy perhaps not unlike our own.
Let's zoom in now on one individual matter clump like this and take a look at another supercomputer simulation. This one has been done by my colleague Matthias Steinmetz in Potsdam, Germany. We're seeing here on the left side a top view of the same thing that we're seeing in a side view on the right side. Here he's put in a little bit more physics, in addition to gravity, also the basic gas physics that's been very well proven and tested in the lab, so no far-fetched assumptions at all. And you start making stars.
And the stars form with these big clumps. And you see the bottom line of galaxy formation is it's not like first our galaxy wasn't there, and then it formed, and then it sat there. Rather, it's been a very messy process of formation, much like a giant series of traffic accidents on the freeway, where every time you think you're done, more stuff crashes in from the side.
In fact, if you look around yourself in the sky in the Sloan Digital Sky Survey we're making, you will see that right now our Milky Way galaxy is busy gobbling up this innocent bystander, the Sagittarius dwarf galaxy. I actually don't know how innocent it is, but that's what's going on.
[LAUGHTER]
And by now, you see it's already beginning to look quite a bit like a spiral galaxy from the top. And you see at the beginning, it was the formation of a rather pizza-shaped disk here. All the red stuff is dark matter. Dark matter is red, at least in your computer, where you can pick a color that you can see.
And although this is very much work in progress and many details remain to be ironed out, it's very encouraging that we can get such a good qualitative agreement between theory and observation. Here is another supercomputer simulation done by Tom Abel and his team, where they've used adaptive mesh refinement to keep zooming in on smaller and smaller patches and get all the way from the scale of a galaxy to this much smaller scale of a solar system. And what happens is you have a spinning gas cloud contracting under its gravity. Again, as it dissipates, it radiates away its energy. Cells into pizza shape, a pancake. Because angular momentum is conserved, it can't collapse into a point.
And eventually it gets so dense in the core, that the hydrogen ignites nuclear fusion, and the star is born. And all the while, gas in the outer parts of this disk is clumped into planets, which become revealed once the nascent star blows away the remaining of this gas disk. Because all the angular momentum came from this gas cloud, it's no surprise that in our solar system, all the planets are orbiting around the sun in the same sense, which is also the same sense that the sun is spinning in the same sense as most of the planets are spinning.
And just to come back home again and put this in perspective, I want to remind you that even our planet is constantly evolving. When I first heard about plate tectonics, I thought that 200 million years was just an awful long time. Think about it. This is less than a few percent of the age of our universe, right?
So this is a very, very brief summary of how MIT got here.
[LAUGHTER]
And since we actually managed to cover 14 billion years in the just 20 minutes, let's take a quick peek at our future as well because we don't have to press stop on the computer at the present time. Here we see our solar system orbiting around in red here, orbiting around the center of our Milky Way galaxy, which it's done about 15 times so far. And in the future, here is some trouble coming.
This isn't the Andromeda Galaxy, our nearest big neighbor. Hold on to your hats. Because although there's a lot of other stuff pulling in the neighborhood here, about 3 and 1/2 billion years from now, whammo. It's not as bad as it looks because--
[LAUGHTER]
--because most of the stars actually miss each other. But we are in a slightly more precarious orbit now, closer to the monster black hole in the middle of our galaxy. Here comes the biggest corporate merger you'll ever see.
[LAUGHTER]
And Milky Way and Andromeda merges into what I think they're going to call Milkomeda, but we'll see what they decide.
[LAUGHTER]
And our solar system is now in a very disturbing orbit here. So maybe we'll figure out some good way of moving to a slightly better place at that time.
[LAUGHTER]
Now, this is a good story. But why should you believe a word of it? The short answer, again, is data. This is Tech Day, so I'm not going to feel guilty about stressing the importance of data and technology and measurement over and over again.
And it's really been remarkable. Science magazine hailed as the number one breakthrough of the year, quite recently, this fact that because of the Sloan Digital Sky Survey and this NASA microsatellite, so we could now really start believing, rather than ridiculing, the many of these cosmological predictions. It's the measurements which have transformed us, just like measurements transformed other things which people didn't used to believe into real science. And we've talked now about the spectacular measurement, just photographs of this plasma sphere, where the different colors correspond to slight differences in how dense it is in different parts of the baby universe.
And just to put this in perspective, on this scale, again, of our observable universe, which is also basically the region of space from which light has had time to get here so far, which is what we usually just call our universe-- so if you want to print out a T-shirt with the picture of the universe, this would be the iconic image you would use. On the same scale, all we've mapped so far in three dimensions is this puny stuff here in the middle.
Let me zoom in on this here. And you'll see the Sloan Digital Sky Survey again, with all these galaxies, different colors corresponding to different types. So we have a long way to go. But already with these rather modest three-dimensional maps, we can do a lot of great physics because we can take these measured three-dimensional maps and compare them with computer-simulated maps.
And the good news is we can get them to agree. We can get the statistical properties of how stuff is clustered to match beautifully. But it only agrees if you put in very specific values for how much atoms there is per unit volume and various other things.
So we can turn these pictures from just being fun things to look at to being extremely useful probes of numbers. And numbers is, of course, what we're all about here. So we call our numbers cosmological parameters. You've come across many of them already.
One set of numbers just tells you what the universe is made up of on average. And we were quite taken to realize, as a community, that only 4% of the stuff is atoms, ordinary matter, that there is about five times more of this invisible stuff we call dark matter, and then still three times more called dark energy. To show a slightly more geeky plot, let me take this number of atoms plus dark matter and plot it on this axis versus the amount of dark energy here, because this inflation theory of Alan Guth, which sounded very frivolous the way I first introduced it, makes some very quantitative predictions.
One of them is that this number plus this number should equal 1 in these units, which means, then, that the truth in this plane should lie somewhere on this diagonal line here, right? Well, does it? For many years, we couldn't measure. Now we can. So Alan Guth's theory is testable.
This NASA satellite came in at first and killed off all of the red area of its parameter plane at 95% confidence. So it's beginning to look good for the prediction of the line here. And the data from the satellite got better. But we still couldn't really be sure if we were here or here.
When we put in our Sloan Digital Sky Survey work, we got this ruled out too. And we can now measure that the sum of the two numbers, which was predicted to be 1 by Alan Guth's inflation theory, we've measured it to be 1.003 plus/minus 1%, so beautiful agreement. And we've gone from arguing about a factor of 10 on the exponent to a 1% measurement.
And there are many other numbers. I promise to not show you too many more. Otherwise I'll be chastised afterwards. We can put good numbers to the different stages in the evolution of our universe. If you're only going to remember a single number when you go back home to tell your friends about, I recommend that i be this one, current age of our universe. [INAUDIBLE]
It's just remarkable. Even when I was a postdoc, we were arguing about whether our universe is 10 billion years old or 20 billion years old. Now we are arguing about whether it's 13.7 billion or 13.8 billion. That's how fast things have changed.
I promise to not just spend the whole time dousing you in numbers. So let's shift gears and talk about something a little bit more philosophical because we don't get numbers alone out of cosmology. We also get a much greater sense of where we are in the grand scheme of things.
So let me pose this question. Is there more that exists than we can see? I already mentioned how when my grandma was young, they had no idea how much stuff was really out there So I made this little plot showing how much we knew existed as a function of year. And it's really been quite remarkable on this crazy log scale here, right, from when people first realized the size of the Earth.
I was in Egypt yesterday. And it was amazing to see Eratosthenes place of work in Alexandria and so on and see how blown away they must've been by this. And then every time we thought it wasn't going to get any bigger, it did. And just in the last 100 years, whew, we've realized that it doesn't stop at our galaxy or other galaxies.
In fact, there's absolutely no reason to think that space ends abruptly here. It's like if you're walking around in the fog, why should you think there's no more space just beyond where you can see? Alan Guth's theory of inflation doesn't just predict that space is big. It actually predicts that it's infinite.
It would be kind of odd if there was a sign saying space ends here. Mind the gap. But take my word for it, there are other ways in which you can envision the space actually not being infinitely big. But this inflation theory predicts infinite space.
So suppose it's right. Then you have an infinite space. And we are using the phrase "our universe" to describe a region from which light can get here in 14 billion years. Then there is [INAUDIBLE] many other such regions, right, which some people like to call parallel universes.
This inflation theory also predicts that there's going to be stuff. There's going to be stars in all those other regions too. It's just that the atoms start out in slightly different places, so slightly different things happen. You can calculate that if you go about a googleplex meters in that direction, you will come to another universe which is identical to ours.
And long before you come there, you'll find some other ones which are very similar looking. There will be a commencement going on in the [INAUDIBLE] Auditorium and so on. It's pretty dizzying thought predicted by this theory, which, of course, brings in the philosophy buster. You have to ask yourself, are theories which predict the existence of unobservable things untestable and therefore not science?
For me, if it's not testable, it's not science. Nonetheless, I feel that inflation is testable. Because for a theory to be-- what we're testing here are mathematical equations. That's what these theories ultimately are. And for it to be testable, we don't have to be able to test all their predictions. We have to be able to predict only at least one, right? Then it already stands a chance of being falsified.
So let me give you an example. Einstein's theory of gravity predicts exactly what happens inside of a black hole if you should fall in. Don't recommend trying it. But at least you can rest assured that you can get a good forecast for what should happen. That's untestable because you can't come back out and publish your findings. But--
[LAUGHTER]
--we nonetheless take this prediction very seriously because that theory the of Einstein makes all these other predictions for why your GPS navigator works the way it works and so on and so forth. So the analogy is inflation predicts space is infinite. If that's right or any other theory that makes an infinite space is right, then you're stuck with a much vaster reality than we can observe.
If you're agoraphobic, I guess that's a problem. But I think if you're claustrophobic, it's great.
[LAUGHTER]
Besides, our job as scientists, of course, isn't to tell the universe how we want it to be, but to figure out how it is. So let me wrap up by looking a bit forward here. So when I was a grad student and a postdoc, we talked a lot about how great it was going to be when we would have these precision measurements that we've flown through and marveled at and how we would be able to use them to measure these numbers, these cosmological parameters.
Well, now we've accomplished quite a bit about that and measured some of them even to a percent-level accuracy. So what's next? To me, the most exciting part lies ahead, which is using these measurements to learn something about the fundamental nature of reality, the fundamental physics that lies behind this.
And as always in science, when we discover something new, with the answer comes a host of great new questions. We've measured how much dark matter there is. But, hey, what is it? We might even find out this year, and I can tell you why if you ask me about it in the question period. We've measured how much dark energy there is. What's that?
We've measured that there were these fluctuations at the 10-to the-minus-5 level in the early universe which were the seas that created all the galaxies. Where do they come from? And why do all these numbers have the values they do and not other values? There are a lot of very deep questions here.
And for all of these three questions here, the nature of dark matter, dark energy, and the early universe, the basic measurements you want to do to answer them is you want to map our universe. And I don't mean just map a little piece of it anymore. I mean map everything we can map. I've mentioned how there were lots of great techniques out there which have already mapped various parts of it, right?
So let me just close by telling you about what I think might be the next big thing in cosmology which can, again, blow away the precision we've achieved so far. This is something which I personally am spending a lot of time on now with my group here at MIT. And it's called neutral hydrogen tomography, or 21-centimeter tomography, which sounds very geeky. And I'll explain shortly what it is.
The goal is to map all of this, everything in this sphere, and look how little we've done. All the galaxies we've ever seen are in this tiny fraction of the volume near the middle. And these baby pictures, the microwave background which gave that Nobel Prize, they all came from a thin spherical shell as thick as this black line here, so again, a very small fraction of the volume, right?
Now, the basic idea behind this technique is all of the sphere's full of hydrogen. Hydrogen gas can give of electromagnetic radiation of a wavelength of 21 centimeters. But if it gives it off in the distant past, when space was much smaller, than these waves will be stretched out and reach Earth at a longer wavelength.
So instead of getting here at the-- they might get here with wavelength of 1 meter or 2 meters, which just tends to be right around the FM band, 100 megahertz, 200 megahertz, and so on. So you don't need any fancy detectors for that, just a cheap radio basically. And with a colleague of mine, Matias Zaldarriaga, we recently proposed that-- actually just last week-- a telescope we called a fast Fourier transform telescope, which you can think of basically as a giant sea of really, really cheap radio antennas hooked up into a computer.
What's the point of that? Well, to be able to map all the hydrogen the universe, obviously you need really, really good sensitivity to get really, really low noise, right And it's pretty obvious that the bigger your telescope is, the lower your noise is going to be.
But big is expensive. For an ordinary telescope, if you imagine taking a radio dish like this and building it a kilometer wide and then being able to have end motors that can point it without it falling over-- who's a mechanical engineer? That sounds pretty expensive, doesn't it? Yeah.
And another technique-- this has been very successful-- is to take a lot of radio antennas and instead connect them to a computer and that way try to reconstruct a map. But for that, the cost goes like the area squared, which is prohibitively expensive. For this idea, the cost scales only as area.
And since this is Tech Day, I'm unabashedly going to talk about slightly nerdy tech stuff here at the very end and use the word Fourier transformer a few times. So I apologize in advance. But I want to give you a flavor for, again, what's really driving cosmology isn't just big philosophical questions, but it's really technology.
A telescope is basically a Fourier transformer. And if you don't know what a Fourier transformer is, which I expect-- which I'm not-- you're certainly not required to, in plain English, this just means that we have this electric field everywhere in space, and you simply want to decompose it into waves. You want to know how much waves do you have of wavelengths coming from different directions. The directions from which the waves come in the sky is what exactly would give you the map, right?
And the length of the waves tells you how much those waves have been stretched out since they were 21 centimeters long and therefore how far away the radiation came from, giving you the full three-dimensional map of our universe they were trying to make. And the basic idea is instead of building fancy, expensive equipment, you just place an order for a million of the cheapest TV antennas from China or whatever. And because of Moore's law, you can now do something which is previously impossible.
You can take the electric field, even at frequencies up to like a gigahertz, and just immediately digitize it. Your cell phones do that for like $3 for the equipment because 1 gigahertz is a pretty slow computer today. And then you can do all the math that the telescope used to do by analog means in software, which is I think the way that all telescopes pretty much are going to work eventually in the future.
And just to put it all together for you here, if you're trying to measure anything in science, the accuracy with which you can do it basically goes like 1 over the square root of the number of numbers that you have, right? And this is roughly how many independent numbers were measured by different cosmological experiments in the past. Early galaxy surveys, this Nobel Prize experiment nailed a few hundred, this fantastic NASA satellite a bit over a million.
And yet, you see, this is a linear scale in time. [INAUDIBLE] the NASA satellite a bit over a million. And yet, you see, this is a linear scale in time versus a log scale in how much information you have. This is like Moore's law again, where every few years, you double how well you can do.
And well, this fast Fourier transform telescope is as much better than the current state of the art as the current state of the art is from the early days. And if you could go map even modestly just not the whole observable universe, but just the band they've shaded here and dark blue, which turns out to be the easiest place to start, this number has now been measured to 1% accuracy. For instance, we could measure it to almost to a 50th of a percent accuracy, which would be very interesting for testing these theories. You can also measure pretty much all other numbers that one cares about with great precision.
So to conclude, I've tried to give you a little bit of a flavor for why I'm so excited to get to be at MIT and work on cosmology. I've tried to give you a flavor for how this field has really transformed from being very philosophical to be very data driven and quantitative. And in the process, we've not only managed to map our place in space and time quite exquisitely, but also been able to connect more and more with fundamental questions in physics.
And last but not least, since this is Tech Day, I have tried to show you that as much fun as this has been, the most exciting stuff in cosmology, I think, lies ahead. So the universe is going to be a very happy place for cosmology.
[LAUGHTER]
[APPLAUSE]
Thank you. Thank you very much.
[APPLAUSE]
MODERATOR: All right, well, thanks so much. And we did actually get a few questions. And I should say I was in the Architecture Planning Department when I was here. So this is way beyond my ken.
TEGMARK: If you're worried about-- if you're worried about not understanding quite everything about the universe, nobody else does either, so it's okay.
MODERATOR: Oh, okay, that's good because the first two questions are about the Big Bang. So one question is, if the microwave background originated in the Big Bang, and if light travels faster than matter, how come the microwave background is still here and is not far beyond us? And then--
TEGMARK: Why don't I answer that question first, then.
MODERATOR: And then that's another Big Bang question there.
TEGMARK: So the answer to the first question about why there's still stuff here, if it would have gone away at the speed of light, is you shouldn't think of the Big Bang as an explosion which happened right here. And we humans have historically always liked to try to put ourselves in the center of everything, right, going all the way back to geocentric cosmology. Rather, what we call the Big Bang is an event in time not at a particular place.
Everything we see was once extremely hot and dense. So wherever you were 13.7 billion years ago, it was extremely hot. So the microwave background ratio we're seeing now was somewhere else in the past. And the stuff which was here then is over there now.
[LAUGHTER]
And then do you want to read the next question? Or should I read it?
MODERATOR: You can read it.
TEGMARK: Okay. If the microwave background originated in-- if the Big Bang was so dense, how come it wasn't a black hole? It's an excellent question. In a sense, it was a bit like a black hole backwards, which is known as a white hole.
[LAUGHTER]
If you just have this much stuff sitting there [INAUDIBLE], it would very quickly collapse in on itself. And that would put a very untimely end to this commencement planning. No, but it was flying apart extremely fast and became less and less and less dense and was flying a part so fast, that for billions of years, just the momentum of the motion was able to overpower the desire for gravity to crunch it all together again.
And we still don't know for sure how it's all going to end. We used to think that-- I was taught, for example, in grad school that either it was going to expand forever and the momentum would win, or if there was a bit less stuff and less gravitational pull, it would all come crashing back on itself in the Big Crunch. And then we managed to measure accurately how much stuff there was, and it seemed like it was not enough stuff for a Big Crunch.
So the article started appear in the popular press saying it's going to expand forever. And we're going to end in a big chill. The world will end not with a bang, but a whimper. But then this dark energy came on the scene, which has this bizarre property that it doesn't dilute.
So now if 75% of the stuff is dark energy, our stuff will dilute. So soon the dark energy will be 95%, 99% and so on. And our future is-- figuring out our future now is actually completely equivalent to understanding what this dark energy is, which is why we want to know what it is.
So if you want to go home and tell your friends how the world's going to end, there are now three options you can give them on the menu, depending on what the dark energy is, Big Crunch, Big Chill, or a Big Rip, where the dark energy makes things expand faster and faster so eventually everything gets torn apart. These are coming in fast and--
MODERATOR: Did you just answer these questions, or are these somewhat different from what you just [INAUDIBLE]?
TEGMARK: Why can we perhaps find out the nature of dark matter? That's a great one. For dark matter-- I think we have very, very-- we live in a very, very exciting time in terms of making progress on it. I would say there are actually four routes to figuring out what it is.
Dark matter is kind of-- it's stuff we know it's there because it's gravitating. So first of all, if we just figure out more accurately how it's pulling on stuff, we can learn more about it. Moreover, though, it's quite likely that it's some kind of particle that just is very arrogant and doesn't want to have a whole lot to do with us.
We already know there are such particles called neutrinos, which when they hit my hand, they'll just go through on the other side. And then it'll go through Earth and go out on the other side most of the time. But some people, including my MIT colleagues, Peter Fisher, Tali Figaroa, Jocelyn Monroe, are building amazing experiments to try to actually catch these particles one in a blue moon when they fly through MIT or some lab. And there's been such remarkable progress, that I wouldn't be surprised if you'll read a big splash about this in The New York Times in the not too distant future.
Another thing you can try to do is make dark matter particles. We know we can make new kinds of particles out of old ones by smashing them together real hard and having the energy rearrange itself in new forms. And this summer is one of the most exciting events ever in the history of physics. The biggest machine ever built for physics will switch on in Geneva, the Large Hadron Collider, which crashes particles together so hard that you might actually have some dark matter particles coming out, which would really revolutionize our understanding of what this stuff is.
And there are also some ways of indirectly learning more about what dark matter is by looking at very extreme locations out there in space. So I'm quite optimistic about the dark matter mystery, which has been kicking around this 1930s, actually being resolved soon.
MODERATOR:
GARVIN: Here's a hopefully simple one. Someone asks, how do we get our hands on a copy of Deep Space Explorer 1.0?
TEGMARK: Type it into Google, great stuff.
[LAUGHTER]
MODERATOR: Someone else is wondering whether there are current alternatives to the inflation theory? And are there plausible alternatives, in your opinion?
TEGMARK: That's a great question. So what's happened historically here in cosmology is that there's always been a frontier of our ignorance, right? And we've gradually pushed it farther out in space, and particularly farther back in time.
Newton was able to figure out beautifully how things moved around in the solar system. But he had no clue why our solar system was here in the first place, right? I showed you a computer simulation of how you can actually make a solar system out of a gas cloud. But then I told that bedtime story to my six-year-old son, he said, but where did the gas cloud come from then, right?
[LAUGHTER]
And then I showed you movies here of how if you start with a bunch of hot gas flying apart, you can actually make galaxies, gas clouds, and so on. But what happened before that? I think we have really great confidence in what happened since our universe was 400,000 years old because that's how far back we can just see and look, right?
We also have very great confidence in what happened since the first second. Because when our universe was a second old, it was about as hot as the core of the sun. And we know what hydrogen does when it's as hot as the core of the sun. It does the same thing as it does in the sun. It does fusion and turn into helium.
Except, of course, it wasn't that hot for very long. And you can calculate that it only made 24% helium. You go out and look how much helium there is in space, 24%. That's remarkable. But what happened before that? That's really the current front here.
The inflation theory of Alan Guth and his colleagues is, in my opinion, definitely the front-runner theory because it's passed a lot of observational tests, and you need to assume very little. There are now many other theories beaten about. One that's getting a lot of attention in the popular press is the so-called ekpyrotic universe with colliding brains. In the science community, I only know of three people who believe in it, and I won't name them.
[LAUGHTER]
But this is still very much a frontier of our ignorance, and we do not know. And I think it's extremely exciting to ask what we can do with new technologies to push that frontier of ignorance into the realm of what we can see. Now, you can't see through this plasma because it's opaque.
But why should that stop you? If you go to the doctor and you want to know what's going on with your kidney, and your doctor says, sorry, you're opaque to my electromagnetic radiation, I can't see, you ask for an X-ray, right? And we know that neutrinos can go right through this. So we can use them as a probe of what happened before.
And the best probe we have is ripples in the fabric of spacetime itself, known as gravitational waves. And there's this amazing experiment to try to detect these ripples in the fabric of spacetime here led by the LIGO experiment here at MIT by this amazing group. And if one can measure gravitational waves of wavelengths comparable to the size of our universe, which you can also do, it turns out, by using this map itself as a detector-- I'm not going to get into the details-- the we'd actually be seeing stuff just like an X-ray in the doctor's office, which told you what happened when the universe was way younger, when it was maybe 10-to-the-power-minus-34-seconds old. And that would really clinch what happened early on.
And this is not some kind of futuristic year-3000 technology. This is something that we have, the technology and principle to go look for today. And if there's appropriate funding for it, I think we might be able to do it in the time scale of a decade or so. So very, very exciting, in my opinion.
MODERATOR: I think we have time for one more question. And there was-- well, there's, of course, this one. But how about this one. With your focus on understanding space and the development of the universe, do you find any evidence of life beyond humans on Earth?
TEGMARK: Great question.
MODERATOR: Ending with metaphysics.
TEGMARK: What a great question. Don't we all wonder. This is another field which has been completely revolutionized. [INAUDIBLE] a decade ago, the total number of solar systems known to exist was one. And now almost every week, you read in the newspaper about new planets discovered around other stars. And I'm also very excited to be here at MIT, where much of this kind of pioneering work is actually being carried out.
So far, we haven't found any planets which have life on them. If you ask me to guess--
[LAUGHTER]
I think I'll make two predictions. I think first of all, I don't think there is life capable of space travel or radio transmission particularly close to us. Because if they were, why haven't they shown up long ago? Now, there are many other planets which are just as habitable as Earth that were formed 3 billion years earlier. So if you let an institution like MIT operate for 3 billion years, surely it'll figure out a way of going out and--
[LAUGHTER]
--opening up other universities throughout the galaxy, right? On the other hand--
[LAUGHTER]
--my second prediction is, I think we're going to-- there's going to be a real revolution in our understanding of this in the next 5, 10, 15 years. Because even though--
[BEEPING]
There's life.
[LAUGHTER]
Because even though we don't have telescopes that are good enough to zoom in on one of these planets and get LANDSAT kind of images, what you can do is you can look at a planet. You can find ones which are in orbit so that they sometimes get between you and their parent star, which means that when they're eclipsing their star, light from a star will shine through the atmosphere of the planet on the way to Earth. And then you can look at the spectrum of absorption lines in the light and see if there's oxygen in that atmosphere, where other molecules which are likely to have been created by some form of life.
I don't think it's at all unlikely that there are lower forms of life, maybe even cows and-- there are many other forms of life which are really interesting that just don't have radios.
[LAUGHTER]
And I'm very much looking forward to seeing what's going to come out from this brand-new field in the near future. So thank you again.
MODERATOR: Well said.
[APPLAUSE]
Thank you so much.
TEGMARK: Thank you so much.
MODERATOR: That was really wonderful.
TEGMARK: Thank you.
MODERATOR: Really great. Really great.
NEWMAN: Good morning, everyone. It's a real pleasure to be here with you. I look forward to our time together. So my learning objectives for this discussion are first to familiarize you with human spaceflight, some of our research around MIT, and really to share my passion for human exploration and aerospace biomedical engineering with you. I'd like to demonstrate my philosophy of teaching and research. It's love, act, discover, and innovate. I think these are essential ingredients for our research and learning activities at MIT.
I'll take you on a journey, not as far out as into the universe as Max. I'll bring us a little bit closer to home. We'll start on Earth. We'll make it to the moon and Mars. And then we'll probably come full circle and come back to Earth again, a bit of personal exploration. And finally, I'll end by celebrating this. And I'm posing some questions to you about innovation and creativity and in teaching at MIT.
So just to start, a little bit of the work we look at from an engineering perspective, but we're very interested in how humans move and how humans perform. You just saw a simulation there, a biomechanical simulation. It's a physics-based model. It's a real simulation of someone walking across the ground.
And we also do work with robots, human and robots. That ties into the next speaker as well. You'll hear Professor Cynthia Breazeal. So we're interested in capturing human motion and then using robots, in my sense, as kind of surrogate astronauts. Can we perform the same motions? Can we control them? Can we make their work easier to perform in very extreme environments?
I also want to highlight some student projects as I go. So looking at design, especially design here on Earth, wanted to show you some work with a collaborator for paraplegic athletes. So to wake us up a little bit after the break, I do have music on this one. It's a collaboration with [INAUDIBLE] and from the Rhode Island School of Design.
So could we design and build a cycle for paraplegics racers that would be the world's fastest? We did aerodynamic testing and the testing with paraplegic athletes here at MIT. We believe that this is the world's most aerodynamic cycle.
As you can see, it's controlled completely with the upper body. So if you have use of your arm, then you can power this cycle. You can steer the cycle. And by moving your body, you can do some pretty nice slalom moves as well. So it was really a great project to get together the engineering students at MIT with some of the design students at other universities and really come up with just prototypes.
As I said, it's actually the world's fastest at this point. But it's still not legal for the Boston Marathon. But we did have--
[LAUGHTER]
We did have the winner and the third place, both female and males, on this cycle to get the data on them. So that's just a kind of a celebration of design. I'd like to move along. And I was early inspired in my MIT with work of other colleagues.
I'm showing you some simulations here from what was then the MIT Leg Lab. So we're pretty fascinated by how humans move. Can nature teach us everything we really need to know-- and animals? So there's some wonderful simulations that Marc Raibert and his folks had done, anything from kangaroos to ostriches.
And then the real mix is, okay, let's see if we can put these humans and robots together. Now, watch his moped robot because this is pretty fantastic. He's going to perform nice little motion for you here. Get ready. Woo-hoo! You're supposed to clap there. That's pretty tough to do.
That's tough to do. This is not just an animation. This is a real physics-based simulation. So that has all the equations of motion embedded in it.
And then just to take you a little bit beyond Earth, well, that's where I spend most of my time and passion. And I definitely wouldn't recommend trying this at home. But let's see if we can get astronaut Dr. [INAUDIBLE] in there.
So what if we really had precision control about all degrees of freedom? We study this. We try to employ it. [INAUDIBLE]. She's smiling. That is a happy astronaut. And if I--
[LAUGHTER]
If I take you to the microgravity environment of space stations, then you see here-- this astronaut Jerry Lindenger. Now, again we're more like floating. We're doing horizontal motion. We have some smart sensors here. This is our design for the smart sensors.
You can carry the electronics in the palm of your hand. And we've flown these on the shuttle, as well as the Russian Mir station. And they're targeted for the International Space Station as well. So we're pretty fascinated with motion and movement and control.
And I'd like to tell you a little bit more about that. This is a collaboration with Professor Hugh [INAUDIBLE] and our graduate student, [INAUDIBLE], who performed that work. So again, we're modeling the muscles when you're firing your muscles on and off. Then we came up with an active ankle foot orthosis, you see here in the video on the right.
This is a patient after stroke. He has what's known as drop foot. His left foot goes down. He doesn't have the musculature to control the left foot. So we put him in an orthotic device. It's a smart orthotics device, so it's actually got a cushion when he slaps down. And then it's going to propel his locomotion.
For the Tech Day part of it, we actually use an adaptive biommimetic torsion spring damper to cushion the slap. We used a minimize impedance controller. And then we're using an adaptive torsion spring damper. Watch him go. It's a learning algorithm.
He has one good leg, so we can take all the kinematics, all the body angles from the right side, and beam them over to the left side. And he would have loved to walk right out the lab. But we had him tethered, of course.
[LAUGHTER]
Hugh and his folks are actually trying to commercialize that device as we go along. So how can we help people on Earth? And what can we learn from some of our extreme environments? We only get to fly an experiment about once every decade in space.
So I hang people from the rafters. And we do things like take the floor out from under you. So sorry about that. You can volunteer to be a subject, if you'd like to come over to our lab. And what I'd like to show you here is actually called a false platform experiment.
So you're going to see a first jump. I'm actually the subject with my graduate student there. I want to test out all of our experiments. We have human use approval for all of our experiments, I would mention.
So I jumped down. I'm wired. We're looking at all of my muscle activity. We're also looking at the kinematics. We're looking at my body angles. And now you're going to see me jump through the floor. But I don't know that they removed the floor. I'm back there listening to white noise.
Now, I didn't fall, which is a good thing. But we're really interested in that posture and control, again, for folks here on Earth that have pathology and disease, as well as for putting people in the extreme environments that I usually study in space. We use control theory and dynamics models. I'm not going to bore you with that.
I do have a little bit of data here. Don't know if you can see this or not. It's quite bright where I am. So this is muscle EMG activity, a neck muscle, the sternomastoid, the neck muscle. There's data here that shows you, the red data, the neck muscle turned off on the first jump when the subject hit the floor. It did anything but turn off when you fell through the floor, a real heightened significant response.
And here we have the kinematics of the knee joint, this bold wavy line here. And what we've proved within the 100 milliseconds that you fell through the floor, in 70 milliseconds, you flexed your knee, and then you re-extended it. That 100 milliseconds is much, much faster than the 250 milliseconds I need to make a voluntary control, so voluntary movement.
So we proved that there's both feed forward controls from the brain down to the arms and legs, as well as a feedback control. So if you're an engineer, like myself, you come up with an elegant model. And you say, wow, for the first time, we've proved this feed-forward feedback controllers. It had been done in cats and animals before. But without hurting any of the folks, just having them fall through the floor, we were able to prove it in humans as well.
[LAUGHTER]
I don't poke and prod. I don't like blood myself. So there's a reason I'm not an MD. I'd faint.
[LAUGHTER]
So as I mentioned, we have to train astronauts. We do a lot of work here on Earth before we get to fly our experiments. So I'd like to show you a little bit of what we do for some of our training.
We spend most of our time training NASA astronauts in kind of large water tanks. Now I'll take you on a ride here. I'm not trying to make you sick. But this is a full shuttle payload bay.
So we go underwater. On your right, you see us underwater. But now we have a treadmill and a lunar simulation that's 1/6 your body weight or 1/6 G. Now, you're at Mars. This is 3/8 loading, 3/8 your body weight. We load the person through the center of the mass of their legs to try to make the most realistic simulation of the moon and the Mars that we can.
Now we're flying in an aircraft. This is NASA's KC 135. But we're flying a lunar parabola. And next comes a Martian parabola. It looks pretty much like bipede locomotion, looks comfortable. The great thing is we can all be marathon runners when they get to the moon and Mars.
Just a little bit of data. This is just force traces, left foot, right foot, left foot. It's normalized. The units here are about three in terms of ground reaction forces. When we did the Mars simulation, it's about half. So it's not quite a linear response, but it is significantly reduced. That's an important part of the story, because we see significant physiological de-conditioning with our astronaut subjects.
I'm going to move on to that. So what are the big challenges that we have in spaceflight? Well, musculoskeletal loss is right up there at the top of our challenges. So again, I showed you some videos in microgravity. We're floating freely. We're not bipeds anymore. We're kind of horizontal, more like snake and swimming-type of motion.
But as soon as we get to the moon, 1/6 our weight, Mars 3/8 our weight, then maybe some things will be restored. But from our decades of microgravity work, we're really trying to do sensory motor investigations. We look at the adaptation. We look at locomotion. And then we try to tell the story about these planets we've never been to before, although we have a little bit of lunar data.
So just from microgravity, long-term spaceflight, now months in space, not weeks, but months in space, this is data from over 30 cosmonauts and astronauts to date. The good thing is, and my astronaut friends don't like when I say this, but you're not losing any bone loss in your skeleton. You actually are gaining it. So you're a little bit thick skulled.
[LAUGHTER]
That goes well with the astronaut corps, as well as a lot of us at MIT. Your arms aren't doing too bad either. We don't see significant loss in bone degradation per month in spaceflight. But all the numbers in the red is what you should be concerned about.
We see one, and it gets close to 2% bone mineral density loss per month in spaceflight. These are very healthy 40- 50-something-year-old folks. So we see muscle atrophy 20% to 30%. We see up to 40% strength losses. That's the good news.
The bad news is that 1% to 2% bone mineral density loss per month for the skeletal system. So now how many of yo are going to join up for my four-year Mars mission?
[LAUGHTER]
This is a micro scan of a bone for a very healthy 37-year-old male. This is a very unhealthy 84-year-old male with osteoporosis. So my job, in part then, is to try to keep the astronauts that go to Mars and the moon not looking like this nice squatty little gentleman down here.
[LAUGHTER]
There's a huge relation to aging. But we have some different bone loss mechanisms. So I'd like to show you a little bit of some of our latest data. We moved to mice because we can study a lot more mice than we can cosmonauts and astronauts in space.
There's a little mouse running over our first plate. It's a work of a recent PhD graduate student, Erica Wagner. So we look at the muscles. We look at the bone. We see a very significant-- this is a Mars simulation. We see a significant decrease in the musculature.
I'm showing you average data from the gastronemius muscle, so very significant bone loss here. In this study, it was over 23%. That's the good news I told you about, right? And now we get to the skeletal system.
So let's take a look at the femur. This is the femur here, if you're familiar. Hip is up here. We go down the thigh. So we're going to take slices and data here at mid shaft and then down toward the distal end of the femur.
Now cortical bone-- you need to know about two types of bone. So cortical bone, just think about that is the outside hard shell of your bone. So I'm just going to draw it here is a cylinder. And our controls should not change.
And then we have a choice. If we're going to lose bone in space, or inside diameter might get bigger, or our outside diameter could shrink, or we could have both at the same time. Well, what's going on? Well, from all of our data both in humans with some limit to human data, and now with a lot of data on us, this is what's happening. The outside diameter is actually-- we're losing it, and it's sheering down.
So we see about a 9% loss in the cortical shell. We have 9% cortical thinning. We have about 30% loss in the bending strength of our cortical shell.
When you take a look at the spongy bone, the bone, all these little struts that make up the inside of your bones-- so again, this is a very healthy control bone. And then here we see about 11% thinning in the trabeculae. So we have a significant musculoskeletal reconditioning issue that we're trying to address.
We've been trying to look at the mechanisms. We're feeling pretty good about where we are with them, understanding what the mechanisms are. And so what are we going to do about it?
Let's just put you on a map here. Here's Earth, 1G. [INAUDIBLE] go down to about 3/8 G here for what the Mars condition is like. And then the moon is about 160. Again, microgravity here is something very different. I've showed you some significant losses.
This is a bone loss graph. Up on the top is the cortical bone, that outer shell, in green. And here on blue are the more significant trabecular losses. Now, it's anything but linear. Life would've been easy if we would have said from 1G down to spaceflight because we've been in microgravity quite a while. We see real significant losses here, the relative changes to 1G, up to 60% relative changes.
It's very non-linear. And we have this interesting potentially dip at Mars, which didn't make sense at all. Why would we lose more potentially to higher gravity level than the moon? Well, there's different reasons for that. And it has how much moving around are you doing? Remember those falling-through-the-platform experiments that I showed you? There's a posture stability.
If you're moving around a lot, you might actually be helping the integrity of your musculoskeletal system. So we're really trying to understand these significant losses. But again, it's anything but linear. And so we're really trying to get into the details of what the mechanisms perhaps are behind these changes that we see.
Just put another plot up here. If you want to take a look at spinal cord bone loss, I put this up just for reference. The first two years we see a very significant drop off in the skeletal loss but then a bit of a plateau. So we're also looking for these mechanisms from our spaceflight data in terms of will we see a plateau? Will we really plateau in terms of our skeletal losses?
We don't know the answer to that yet. We haven't had long enough to study it. And we haven't had enough subjects to actually fly. So that's why we use the mouse model.
So on one slide, I kind of have a dense summary here but to tell you everything we know about from the last decade or so for the musculoskeletal reconditioning. Here's the reason. We have a negative calcium balance. So per month, we're losing about a half a percent.
It is a bit site specific when we look at bone loss, especially to the vertebrae and the longitudinal bones of the legs. When we take a look at the biomarkers from the astronaut/cosmonaut data, we see an increase in bone resorption. And then we use our animal studies. We see a decrease in the bone formation.
The good news is we see pretty much full cortical bone recovery, that outer shell. But we're not seeing the recovery in the trabecular bone. And that's a link, again, to aging and to a bit of the mechanisms between osteoporosis.
The cortical thinning, again, close to 9%, that really caused by that outside diameter becoming smaller, not the inside diameter. So we see a change in the outside diameter. That's different than in the case of aging. In the natural case of aging, your inner diameter is going to grow larger, but your outside diameter is also going to grow larger.
So aging is actually an appropriate skeletal response. It maintains the material properties and the bending strength. From our spaceflight data, when we look at the trabeculae, the trabecular deterioration in terms of the bone volume over the trabecular volume, we see this 20% thinning, 11% in the actual numbers of the trabeculae themselves. We see a significant reduced bone formation rate. That's really due to the loss of the mineralizing surface. It's not a reduction in the osteoblast. That's kind of the bone-building number.
We do see a very significant reduction in bending strength, close to 30% in the ultimate moment, is really due largely to the geometric changes. And then muscle atrophy, again, close to the 20% and more changes, depending on what muscle you look at. Now, that's not just because we're in an unloaded environment. A lower gravity environment can't explain those significant muscle losses.
So what would we like to do about this? It's significant. The data I've shared with you from astronauts is with exercise. It doesn't get us there. Some pharmaceuticals, some bisphosphonates are promising. But we're really looking much more into assistive suits and artificial gravity.
So you saw the artificial gravity sleeper from our lab on. Now you can see human-powered artificial gravity. This was actually an undergraduate project here with students. So you pedal and pedal. You never catch each other. But we can pull about three Gs on this. So actually, I was worried we're going to fly outside the lab there. But it really works well.
On the left is an a shoe pedal design, if you will. One of the ways we might be able to address this musculoskeletal reconditioning is actually by providing you with high frequency. About 40, 50 Hertz would be very nice. There's some very nice work by Clint Rubin and folks in New York.
Again, it's not becoming a power lifter. That probably won't do it for you in space. We've been doing that for decades, and we really haven't attacked this problem. But if I put you on a vibrating platform, in this case, we actually put the frequency-- think about it as a foot massage, if you will, while you're spinning away on our artificial gravity device. That might be what we call the ultimate countermeasure.
Using artificial gravity, you're basically loading yourself. You have one body weight equivalent at your feet. And if we give you this little vibration at the feet, we might be able to really not see any of these deleterious physiological effects. That's the hope. But we still have a lot more research to do in this area.
So I'd like to move on to some interesting environments. We get to fly with NASA, so their weightless aircraft, affectionately known by the students as the Vomit Comet. This astronaut, Cady Coleman, is performing our experiment with us. This is how we can truly simulate the space environment, less going with a spaceflight experiment.
So it's a very useful aircraft to perform our experiments in. These are smart sensors, force and torque sensors here. And again, you can see the motions are a little difficult. We're kind of losing markers up there. We're floating around trying to catch her markers, not an easy laboratory to perform science in.
So that was to try to quantify the motions, the motion strategies. It's great to do one-handed push-ups, though. Everyone can be a-- here we go. We're trying to again these smart sensors. We're trying to look at different motor control issues, as well as the movement of all the limbs and joints.
Everyone has little weight bags in their pockets. When you don't feel good, you just relieve your stomach and you just keep going on with the experiment. So it's pretty expensive to fly in this airplane. And you get a little bit adapted. It's always better the second, third, and fourth day.
But it's a little bit-- it's definitely an extreme environment to perform your experiments in. So if we get all of our science and all of our data, then usually at the end we can have a little bit of fun up there. I obviously need to have a little better motor control and posture control.
So now what I really want to show you is the students are kind of the stars of the program. So let me see if I can get the-- you might have heard about spheres, Professor David Miller, colleague in aero astro. This is-- we just started this as a design project for our junior and senior engineers. If we can have the sound a little bit up on this, it'd be great.
[VIDEO PLAYBACK]
- --in your new hirees. And they said, we would like to see hirees that have the full lifecycle experience in developing an aerospace product.
- We're trying to make our conceive design, implement, and operate the context of an engineering education.
- So we came up with this course, which is really a three-semester course. And it started basically with a clean sheet of paper, where we gave them a problem, something to build, gave some requirements. And they took it from there, built the thing and are now operating that facility in NASA's 0G aircraft.
- The students were presented with a basic concept and allowed to run with it in their own pursuits.
- The concept is that instead of building large expensive satellites, we can make them cheaper by perhaps building smaller ones and coordinating their activities. On the KC 135, the real goal is to see if we can predict how our algorithms will work in an environment other than that in which we designed them. So we can't do that in the lab. We can't test in 0G. But we can design controllers, go up on the KC 135, see how to behave in 0G, and see how our predictive capability is.
- They did pretty much what they were supposed to do. You lift it up and let go, and it stabilizes itself. So we demonstrated that, which was one of the goals of the flight.
- I think that we got some good data on both what the sphere is doing and on what the plane is doing, because the plane does some pretty extreme stuff, and that what the plane does also affects how our experiment works.
- I was telling somebody the other day that if we're in a group walking somewhere where I have images of The Right Stuff floating in the back of my mind. And everybody I tell about the project, their jaws just drop.
[END PLAYBACK]
NEWMAN: And then he goes on to say, and only at MIT. So really, the students are the stars here. This is a really interesting educational experiment. Today, spheres with the PI Dave Miller is a full-time International Space Station experiment. It started really in our laboratories with 15 brave juniors and seniors who said, let's give it a shot. We'll go from clean sheet paper. We'll work on this hard, and we'll build something and design it and really be able to fly it for NASA. So it was a great experience.
Here we are, too, just wanted to show you a little bit of some of the where science meets engineering, because we really do want to see how the brain is controlling the motion. And so here's a little bit of our approach for motor control and adaptation for this altered environment. So our null hypothesis is that in our brains, then, essentially we have these internal models and feedback control to make these sensory motor adaptations for these altered environments.
So as engineers, then, we apply adaptive control models of the motor system. They're very robust. They're physics based. They need to work in a 1G environment. But they need to work in microgravity as we're floating. And we need them to help predict lunar and Mars performance as well. They incorporate both position and velocity feedback.
Our latest models actually use an unscented common filter for all of you engineers out there so that our central nervous system motor control models right now are accounting for all of the system nonlinearities. They're physics based, just F equals MA. You never never, never get to leave that. And again, trying to look a little bit of at the sensory motor inputs, and then we go full circle and put some Bayesian optimization to take a look at the visual motor performance.
We borrow from robotics theory. But we also try to enhance a bit of the robotics theory. Humans are very complicated, intimately complex. Well, we'll hear from our next speaker how complex robots can be. And we want to make our models biologically relevant.
We're just touching on it. Of course, we're not replicating nature by a long stretch. But we're taking our engineering methodology and trying to design these experiments. It goes from the hardware and the software, these kind of force torque sensor suites. They're very modular. The astronauts can just pick them up and move them where we want. They evolve as the astronauts need them to.
And then we kind of sneakily take a lot of science in the background as well, as they're just going about their daily business. The one of the real ideas behind here, that I'll just stop and mention, is kind of dual adaptation. We think it's possible for me to be a biped and walk around here and be adapted. But as soon as I put you into space, you're going to bump around a little bit, like you've seen in the videos.
The simple example, if I were to take an M&M and toss it out to you right now, I would account for a parabolic trajectory. If I were really good baseball player, I could do that really well at 90, 100 miles an hour. But when you get into the microgravity environment, it's going to go in a straight line.
Now, how quickly can my motor control and my brain adapt to that? We think it might take about 30 days, about a full month to completely adapt to this new environment. Now, it takes a young child a year to two years to get those motor programs down. We think with adults you can maybe adapt on the order of about a month. And now you have performance that's more akin to an elite athlete.
And finally, we think that you can have dual adaptation, that you can adapt to different environments and kind of keep those motor programs in your brain and basically turn on one if you're an astronaut in microgravity. When you come back to Earth, you're going to have to switch back to your Earth programs. And again, it takes weeks to maybe a month to when you come back to Earth to get everything going right.
The funny things are when the crew come back, they're brushing their teeth, and they just let go of the toothbrush, and it falls down.
[LAUGHTER]
They're combing their hair, and they forget about things because now, boom, they're back. And so they have to re-adapt to the Earth's gravity field. But we think that the brain is just so beautiful and complex-- we don't understand it-- that you can really adapt to these very different type of environments.
So I'll move along here. And let's see you where I take your next, still in microgravity. It's one of the hardest problems we hadn't solved up until our most recent graduate, who just walked yesterday, had everything to do with angular momentum and conservation. So this is a good tie into the universe, to Max's talk, in terms of just the individual astronaut. Now, how can he do that?
I showed you before the different axes, because you have to conserve momentum. Now, in the models so far we have about 37 degrees of freedom in the current models. We put in the dynamics. We put in the motion. And then again, we're just touching the surface of what sensory information, what's the central nervous system doing to control?
We use quantized and optimized control methods. And the real trick here is we can replicate the motion. And we kind of break it down into different motion primitives. So you can spin this way and rotate this way. Now, why is this important? First of all, for training, again, for astronauts, but hopefully for some pathology on Earth as well, as we can really break these into the motion primitives.
And then once we go into EVA, Extra-Vehicular Activity, we have our spacesuits on. You're stranded away from the craft. Your little jet pack-- we call it the safer. The jet pack doesn't work anymore. Can we train someone to make a safe return? We think we can in terms of kind of decomposing all of these motion perimeters and then training folks into how to get about.
So we're making a lot of nice progress in that work and very nice work of Leia Stirling. She walked yesterday with her PhD. So getting toward the end of my talk. And so I want to take you into the world of spacesuits. This is just a little infographic.
All these white dots up here are the-- in humankind, we've performed over 500 spacewalks, extravehicular activities. Our first mission to Mars is going to be over 1,000. So we have 40 years of experience. The first mission, boom. So I argue that we need a pretty new revolutionary design.
We've always flown in a gas-pressurized shell. The great thing is it keeps the crew alive. But it's not too creative, I would argue. So when I talk to students about what should the future of spacesuits look like-- I had a lot of help in the '60s. Look at these folks at the Applied Physics Lab at John Hopkins.
Now, who's to say a spacesuit shouldn't be a white spherical ball? They don't need to be all white, Michelin-looking suits, right? No. This is pretty creative. I'm not sure about practical, but creative.
[LAUGHTER]
He's in Apollo arms and legs are kind of hung off this spherical shell. There you see. So it has pretty good flexibility in terms of the arms and the legs. And he's just going for-- it's kind of the hamster cage approach.
[LAUGHTER]
Not too bad. Not too practical. But if we want to think out of the box, why don't we think of some designs like this? That's what I always urge my students to take a look at.
So then we move to another, what I think was a, really great idea way before its time. So now we move to 1970. And this is Paul Webb's space activity suit. So this was the first time that mechanical counter pressure, basically shrink wrapping, the astronaut was ever tried. And a lot of our work is really motivated by this.
So he has a pressure suit on. He's doing all right. He has a shell. Look at that he's climbing up that treadmill no problem. It's pretty mobile.
Now, the thing was this was way before we had the materials and the analysis tools that we have today to use, because, as I said, this was really in the early '70s. NASA didn't go there. But I think it was a very creative kind of revolutionary idea. It really helped our work a lot.
So in the lab, we do do a lot of work on the current suit, current robot and current suit. We drive it with the kinematics. The current suit, just to let you know, is 140 kilos. When you're in microgravity floating around, that's no problem. But we can't put you in a suit anything like this when we're going back to the moon and Mars.
So we have to provide you with maximum mobility. And I want to have minimum energy so that you can really do what you're supposed to do. You're supposed to be an explorer. So get into a little bit of the research then we're looking at.
Again, looking at the energetics and the gravity, you've seen our moonwalk, where we kind of hang people from the ceiling. You can also use similar devices for spinal cord injury to unload people to try to get their gait patterns, try to get their gait patterns back up and going. So we look at the energetics. Now, again, this is much more geared to the moon and Mars. Let me get this video going here. Again, it's in our lab. We call this the moon walker.
There's a graduate student. Now, of course, this is at 1G. He's on a force plate, again, embedded with ground reaction forces. So we're taking a lot of measurements. We also take a look at the energetics, put energetics on him, see what's the cost of transport? Now, that's for a Martian stimulation. And we're saying, what's the cost of transport? That's a normalized cost of energetics.
We've collected a lot of data to say how you'll be on the moon and Mars. And then we get into exoskeleton design. I don't get a spacesuit in the lab every day. So we design our own. It's, again, another collaboration with Hugh [INAUDIBLE]. Now, see this loping? That might be the most efficient. There you go.
Looking at all your oxygen workload energetics, it turns out you can all be marathon runners on the moon and Mars. When we look at the lunar and Mars data, we have a very significant reduction here in cost of transport in just four to six units and joules of kilograms over meters. The 1G data points are way up here, especially if you're suited.
So we see a significant reduction. That's very good news. We'll continue our work and looking at suit design and the energetics that get us there. Oh, this one has sound. So I'm inspired definitely by The Incredibles. Actually, we were doing our work before The Incredibles came along. But it's a good tag line for some of our most recent work.
So the biosuit is a mechanical counter-pressure system. We actually are kind of shrink wrapping, providing constant pressure through the entire body. And we take a systems engineering approach. We look at the design lifetime.
The idea is that's a custom-fit suit for everyone. Everyone gets their own suit. You see a couple of our mockups here. We have space and Earth applications. Obviously we'd love to see folks be very mobile and be able to explore when they get to the moon and Mars.
And our most recent project is actually looking at children with cerebral palsy with a similar type of smart suit for their little lower legs. Because if we can put in normal gait or normal locomotion patterns when these little folks are just infants to two years old, again, back to this idea that they can adapt and that their brains are very plastic, and if we can provide normal gait, maybe they will have normal more normal gait patterns for the rest of their lives. We can't cure the cerebral palsy. But we really think we can help people move around. And so we're just starting work in that area right now.
Some of our research results-- I know a lot more about the skin than anyone should for an aerospace engineer. But the last 10 years, we've been mapping the body in motion. These are some skin strain field maps. On the top are the circumferential maps. Going this way on the bottom are longitudinal maps.
We use a 3D laser scanner with our folks out in Natick. You get to get dressed up and color your legs. And then we look at the movement. And this is so that we can design a system that will give you the same stress strain profile as your normal skin does, quite a challenge. We're not quite there yet. But we've made a lot a lot of progress.
Our patterning comes from some analysis that I just have a quick little video of here. Imagine if you drew circles all of your body. And believe me, my graduate students have. We would like to do it digitally now. But draw circles all over your body and then move your arms and legs.
If you move your arms and legs, those circles-- you start with your circle. It's going to change, transform into an ellipse. But watch my two red lines. I have two red bisected diameters. See, they don't change. And this is an exaggerated ellipse for just normal human movement.
Now, just imagine you tie all those red lines together, something I call lines of non-extension. Probably the collagen-- perhaps the collagen in our skin might be laid down in this very interesting pattern that is a bit structural. If that's true, then I can get the patterns for the biosuit. And that's how you-- it's nothing to look like a Spider-man suit. It's to really say that do we have a very special patterning? Because again, I have to provide 30 kilo pascals or a 1/3 of an atmosphere to keep someone alive in space.
For medical applications, like, if you have compression stockings or [INAUDIBLE] those, you only need-- that's easy. You only need a 1/10 of an atmosphere, 10 kilo pascals. No problem. That's easy for us. You can jump into one of my suits here and get that. But it's very hard to keep an astronaut alive on the moon or Mars.
So we get our patterning from some of this mathematical analysis. We're looking, again, for maximum mobility and trying to minimize the energy consumption. And we also need to-- now where the point where we're incorporating some active materials into the design of our suits, kind of think of that as kind of smart zippers.
So we've come up with a digital design from-- it's been a really wonderful collaboration with some international partners in Italy and now most recently in Portugal. We're looking at mobility, locomotion, definitely inspired by designs from nature. We go from our CAD models to the 3D human scans.
We incorporate these this patterning for these lines of non-extension. And just in the mockups, as you see up here on the stage with me, they're my size. I have about three graduate students, who just graduated. They're about my size as well, fortunately. We have about 340 meters of that patterning, those lines of non-extension, and the primary and secondary lines. Some of them are biosensors as well, and they kind of take your performance, your heart rate, and metabolic expenditures as well.
So some of them are smart. Some of the patterning or these lines work to really provide the internal structure, if you will, to carry the pressure. I wanted to spend-- I'm getting toward the end of my time. And so I put in a couple of outreach and educational slides. We're excited. We want to get everyone here excited.
It's a great opportunity for alum to see how can we really send our message of science and technology out to kids, kids in the US and worldwide. So here you see something we call the knowledge station. It is-- well, the prototype is actually a physical device. You see one of the students in there kind of waving her arms and it's a gestural interface.
And the story is I find all kids are excited about space exploration. And so what do they need to-- they're controlling an astronaut on the screen there. And if we can get them really excited about the story-- I'm sorry about that. I jumped ahead one-- about the story of exploration, both here closer to home and the International Space Station, going to Mars, and then we go out as far as Europa because Europa's a really interesting moon of Jupiter to try to look for the evidence of life.
And I'll leave it to Max to take us out to the universe. But the point here is we're trying to get out get out to kids, make it exciting, and really try to increase the STEM activities. And then getting close to the end of my talk, kind of just a one personal slide. [INAUDIBLE] I had a chance to actually sail around the world. Talk about exploration in extreme environments.
I think all the colleagues that we were at nice, beautiful, sunny places because you only take pictures when you're in the sun. But this was really a, for us, kind of a personal exploration of survival. We taught hundreds of children, kids, usually middle school to high school kids, around the world. And we were really interested in talking to them about exploration, but exploration by sea and space.
All of these kids are kids grow up in islands. And they know a lot about living in isolation, living on islands. And they've really never thought of space travel. But we submitted to them that it's very similar. When you're living on a boat, two people on your own, you have to have all of your supplies. It's very much like a spaceship, when you have to bring everything with you to the moon or to the Mars.
You have to have a lot of navigation. And you really don't want to make mistakes. You usually don't get a second chance. So there's a video playing here of [INAUDIBLE]. We're in about-- oh, I don't know. Those are probably only 6-meter seas, not the worst, can't bring the video camera out when it gets much worse than that.
So it's a nice sunny day but kind of rocking and rolling, I believe, there off the coast of Columbia. Everything broke. We had to repair everything. We got it back together. And the real beauty of the trip was to meet different folks from all over the world.
This is a picture from some Kuna Indians off the San Blas Islands. And it was very interesting to speak with them and to learn a little bit about their culture. So that's kind of a personal-- a bit of a personal exploration here on Earth.
And then to close up my talk, I just thought you might have some questions. I also wanted to push you a little bit. This is kind of audience interactive participation time. When I think about where's the next breakthrough going to come for both teaching and research, these are some of the things that I think about.
I want to give attribution to Bob Casanova, who had had a wonderful time thinking about this. So what is revolutionary? If we look through history, genius is often in generalities, sometimes not the details. New ideas often illuminate a pathway towards a significant expansion of knowledge, inspiring great leaps forward, triggering a real transformation of intuition.
Creative paradigms are often simple, elegant, even majestic, and the result of non-linear orthogonal imagination. So I really think at MIT we need an environment for creativity, imagination, innovation. I think we're very lucky that we can really provide that to our students and our colleagues. And I hope that we continue because I'm looking for a lot more revolutionary innovation things to come.
Visionaries seem to be able to intuitively comprehend the mysterious. And the visionaries and great thinkers that I've tried to study might have a common trait in the ability to transcend life's experiences and make these leaps of vast intellectual distances to set a new course. So I think it's all in our imagination and not in intimidation-- imitation, sorry about that.
And I'm going to wrap up my comments there. I think I have some minutes for questions and answers about anything I've been able to share with you. Wanted to take you from Earth to the moon and Mars and then back here again home to MIT. Thanks for your attention.
[APPLAUSE]
MODERATOR: Well, thank you so much, Dava. And your talk generated lots of great questions. And they've come kind of in two forms. One is extended concern about what really happens to astronauts and the people who are in space, and then also some questions about the applications of that knowledge back on Earth.
So one question is, what is the mechanism that causes bone loss in space? Is it lack of exercise? Or is it something else? And then the question is, what does that imply for lack of exercise for people on Earth, particularly as they age?
NEWMAN: I'm going to come out here, if you don't mind. [INAUDIBLE]. I'm not used to tagging between the podiums. I'm about the same size as the podium. So here I am. And I'd much rather interact with you. So that's why we kind of have a unique laboratory in terms of when we go to space.
So the mechanisms, we see some similarities. As I said, we don't have it nailed down for spaceflight. We're just getting at the level of trying to understand is it bone formation, or is our brain shutting off bone formation because we're flying around now?
We think that that's not the case. We thought just to a year or two ago that was the case. But recently we think that no, we're still building bone. But now we have this reduced geometry, if you will. There's not enough surface area there.
So even though we're building bone, and we're still taking away bone, it's really a resorption in a formation issue that's going on. So we see geometrical changes that are causing this very significant bone loss, a month of spaceflight, 1% to 2% loss. And again it's longitudinal. So we see a lot of light loss in the vertebrae. We see a lot of loss in the legs.
These are areas we're very concerned about for Earth as well. Being thick skulled and the arms, now why would it be that we're not losing bone in the skull or the arms? Well, just from seeing my videos, and you're probably seen a lot of [INAUDIBLE], well, you're moving around. You're actually very active with your upper arms. And we have enormous fluid shift.
It's all integrated physiology. That's very complex actually. So there's no fluid shift. You feel kind of puffy faced when you go into space. So we're unloading the legs and the spinal column. But you do see this fluid shift in the face and the brain. And so maybe that pressure is not too unlike when I'm trying to provide pressure to keep someone alive.
So maybe the skull and the upper body and the arms are not losing bone because we still have some restoration here. But definitely the lower legs and the spinal column are losing bone. So then the tie here to Earth and exercise on Earth, absolutely, it definitely has to do with exercise, how much force one body weight-- I'm walking around and putting one body weight each step. You take thousands of steps a day.
So if we get less mobile, we're not doing the natural thing that our muscles and our bones need to do to stay rejuvenated. Now, as we age, though, as I mentioned, there's the bones do change. But it's an adaptive change. It's actually an appropriate change.
But we do become more susceptible to fracture. So if we can take a look at our astronaut population, again thinking about going to Mars and look at risk of fracture, we hope they don't fracture. They're going to be in a spacesuit. Hopefully it'll be a lighter space suit, if we have anything to say about it.
But it's still going to be a spacesuit with a lot of life support on it. And if they fall down, are they going to fracture? Well, we want to know everything we can about that problem because they'd really actually like to say, okay, now at 1G, can we really understand the fracture mechanism and the fracture healing?
MODERATOR: Great. I think there's a follow-on question to that. And that's, how much G would be needed to minimize or to maintain bone density? And could you counteract it by subjecting them to normal G levels or higher G levels? Would that work? And then someone noticed your tag about drugs might be a solution. So they want to know--
NEWMAN: Okay, we'll try to get that in. So how much G? Well, we've evolved and developed on this planet and in 1G of gravity field. So we're very used to that. We're optimized to that. That's why I show you artificial gravity.
If we recreate the 1G loading level at your feet, is that enough? We think that would be enough. But we collaborate with MDs as engineers because we don't know the prescription. If I gave you a half a G, half a body weight loading for 30 minutes a day, would that be enough to keep your skeletal system intact? So we really don't know what the Rx is, or the prescription yet.
But exercise enough is not-- for our spaceflight astronauts is not enough. We know exercise is not enough. So now there's some drug tests going on. There's a lot of bed rest studies going on at Earth. We can take people in bed rest. We can tip them down six degrees so you get this fluid shift. You feel kind of stuffy in the head. You're unloaded on your feet and your legs.
And then there's control groups, and then there's groups doing exercise so that we can really know how much you might recover. But how long, we have to perhaps use spin artificial gravity. How much body loading we need and how much exercise we know that we need, we're not quite there yet.
In terms of the pharmaceuticals, again, the bisphosphonates seem to be working the best for osteoporosis. But again, it's a slightly different issue. They're probably not going to hurt, which is good news for the astronauts. But they're not-- that's not the whole solution. We're just not quite there yet.
MODERATOR: I think those are [INAUDIBLE]. I think we've got time for two more if we have short answers. So here's one or two that go together. We know that cosmic rays destroy brain cells that helmets can't shield. How much are we accounting for brain loss? And then the other question is, is anyone working on mental health of astronauts?
NEWMAN: Those are actually two great questions. Thanks for those, because I've kind of concentrated in some of the musculoskeletal system. If I had to give you the four showstoppers for human spaceflight to, say, something as challenging as a four-year Mars mission, now that includes 600 days on the surface of Mars, radiation, radiation exposure is right up there at the top of the list. So we have to protect our crew.
But I don't think we're going to do it in the suit. We're going to do it in safe havens because we're really-- you really need to worry about galactic cosmic rays when we go out further and can be very damaging. So it's more of a matter of designing incredible rovers and safe havens that you can really shield. Because if you put all that shielding into a suit, obviously it's not it's not mobile anymore.
So water is a great protection for radiation. So if you're in your habitat or your rover and you're shielded, we might be able to address the radiation issue. There was a question about mental health. Human factors and the psychological factors-- again, my top four list would be radiation, would be musculoskeletal, perhaps immunology, and then the social psychology of it, the psychology of it, the human factors.
You're locked up in something probably smaller than your bathroom with four to six of your favorite friends for close to four years. You want to get in that suit and go explore. You are in a small craft. And NASA's done a really good job at selecting folks. But there's been some episodes, and I have to say that in the history of human spaceflight, NASA has paid less attention to that. And the Russians paid more attention to that.
They had some early explosions, physical explosions, fights, things like that, and said, wait a minute, got the docs involved. And so it really is important, too. We need these missions to be successful. We really have to look at crew selection. And the best probably way to do that is do some analog training.
And so locking people up in boats to sail around the world, having them in Antarctic doing exploration, doing different things like this, I think, is really important, the crew mix and, again, their mental stability and working together in teams because again, they're there hopefully, if we have something say about, it it'll be globally. There'll be world cooperation. And we need to get on with our business of exploration.
MODERATOR: Great. And one last question. The first part of it is, do you think that human travel to Mars is safe and practical at this time? And then the bigger question is, will humankind ever truly leave the Earth or the solar system? What are the limiting factors?
NEWMAN: Well, first one first. Of course we will. I think we need to. I think we're very short sighted if we're not going to Mars. We right now have a 2030 vision for the US. I hope we go internationally. It only makes sense to pool resources.
In my lifetime, it is a bit disappointing to me that we went to the moon. That was not disappointing. That was fantastic. That's partly why I'm here in front of you as an aerospace engineering professor. But in 40 years, we haven't been back. That's disappointing.
We have the technology. We can keep people safe. The moon is only three days away. Boom. It's nothing. It's there. Mars is tough. That's why we're looking at Mars.
Mars is a step change. I'm not kidding you that Mars is challenging, significant. But we're up to the task. I know we're up to the task. We can do it with conventional launch and rocket. It would be nicer if we had some fancier propulsion systems. People are working on them a little bit.
And so we can get to Mars safely. I think we can keep people alive. I also think we have to be ready to accept that maybe everyone doesn't come back alive. So that's just the business of exploration. When we first went to Antarctica and all around the world, we didn't bring back all the crews.
So we have to help educate the public that this is like being a fighter pilot, a test pilot. We're going to different places. What's it worth if we can really find the evidence for the origins of life 3, 4 billion years ago on Mars? It's huge. That's huge. That's a huge thing I think we should be up for and go explore.
In terms of humans going beyond our solar system, I think right now I'll leave that to the cosmologists. I think exploring our solar system with people and robots-- so this is a great segue to the exciting talk we have coming up. The human's going to be in the loop. But if I'm here at MIT or in mission control or a space station or perhaps on Mars, it's just a question of where the human's located.
The human is there making the decisions. As robots get more and more capable, then absolutely, we should be sending robots into these extreme environments. And they can accomplish a lot. But when we're trying to find that fossil that shows the evidence for life, I think it's going to be human teams working with robotics to really do the bang-up science that we need done. And that extends all the way out, like I said, to the moons of Jupiter and beyond. But that's as far as I'm ready to send people right now on taxpayer dollars.
MODERATOR: All right. Thank you again, Dava. That was really great.
[APPLAUSE]
NEWMAN: Thank you.