IN QUEST OF INFINITY – 12

By Prof. G. Venkataraman

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Previous Articles In The Same Series
Part - 01	Part - 02	Part - 03
Part - 04	Part - 05	Part - 06
Part - 07	Part - 08	Part - 09
Part - 10 Part - 11

 

Loving Sai Ram and greetings from Prashanti Nilayam. I must first of all thank the many readers who have taken the trouble to convey their reactions to this series; for me personally, this is most encouraging. Many are impatient to get to God! Believe me, everything I am telling you right now is all about God and His Omnipresence! However, there are many subtleties where Divinity is concerned, and we must get there step by step. Meanwhile, I do hope you are finding this journey and the quest we are involved in to be exciting.

Artist's depiction of oscillating strings: the heart of every string theory so far...

One month has gone by since we last got together, and it is only appropriate that I begin with small recall of where we had reached last time. It all started with our going on a grand tour of the Universe. We then tried to enquire into how the Universe came into existence and that, we discovered, required us to brush up a little bit about the basics of physics of the small.

After that we found out that till recently, even big-shot physicists did not know much about microscopic world, and are only recently beginning to explore it with great intensity and much passion. Part of the reason why such studies are being undertaken only now is that when one starts looking at the basic building blocks of matter, experimental studies become very difficult. They also become very expensive, making it necessary for many countries to get together to perform such experiments.

However, to recall briefly the essence of what we covered in the last few issues, the big shift is that physicists have now started building up a picture of matter based on tiny strings rather than particles. This is what String Theory is all about. String Theory started on a rather modest tone and at that time it was hardly noticed; quite normal. Then came many jumps and exciting developments and soon many young bright “kids” began to enter the String Theory arena, because it was full of elegant mathematical challenges. This may sound very strange to you but maths has a great beauty and charm; it may be called the “classical music” of science.

The “elders” of particle physics who in the beginning ignored all this and then became condescending, now began to turn cynical, asking, “So what good does all this do? String Theory has not helped in understanding anything specific and spectacular in physics. Big deal!” Well, that bridge could in fact be crossed in the not too distant future, and this issue is going to start on that part of the story. In brief, it is going to be about what String Theory has to say about the ultimate fate of the Universe.

There are many ways in which this connection can be presented; I wish to do it basing myself on a very interesting book I recently came across. This book entitled Endless Universe – Beyond the Big Bang is what I am going to base my narrative on. There are, of course, any number of books and later, I shall cite some of them. The book I am drawing from is perhaps as good as many others; I am using this as the template because someone was kind enough to give that to me as a gift [!] and it certainly is most absorbing.

This book has two authors, Paul Steinhardt of America and Neil Turok from England . In the beginning, they did not even know each other; each entered Physics with his own personal interest but destiny brought them together against a background of a series of international events and these events illustrate beautifully how Physics evolves by people with very different talents and perspectives coming together. By the way, this often happens and one of the classic examples I can think right off the bat is the incredible discovery made by Francis Crick and James Watson of the structure of the DNA. I am sure you must have read the amazing story of that discovery in Watson’s immensely popular book The Double Helix.

	Prof. Paul J. Steinhardt Paul J. Steinhardt, the Albert Einstein Professor in Science at Princeton University , is on the faculty of the Department of Physics and the Department of Astrophysical Sciences, and Associate Director of the Princeton Center for Theoretical Physics. He received his B.S. in Physics at Caltech in 1974; his M.A. in Physics in 1975 and Ph.D. in Physics in 1978 at Harvard University . He was a Junior Fellow in the Harvard Society of Fellows from 1978-81 and on the faculty of the Department of Physics and Astronomy at the University of Pennsylvania from 1981-98, where he was Mary Amanda Wood Professor from 1989-98. He is a Fellow in the American Physical Society and a member of the National Academy of Sciences. In 2002, he received the P.A.M. Dirac Medal from the International Centre for Theoretical Physics. Steinhardt is a theorist whose research spans problems in particle physics, astrophysics, cosmology and condensed matter physics. He is one of the architects of the ``inflationary model" of the universe, an important modification of the standard big bang picture which explains the homogeneity and geometry of the universe and the origin of the fluctuations that seeded the formation of galaxies and large-scale structure. He introduced the concepts of "quintessence,'' a dynamical form of dark energy that may account for the recently discovered cosmic acceleration. He has also explored novel models for dark matter. In condensed matter physics, Steinhardt and Dov Levine (Technion) introduced the concept of quasicrystals, a new phase of solid matter with disallowed crystallographic symmetries, and Steinhardt has continued to make contributions to understanding their unique mathematical and physical properties. Recently, he has worked with Weining Man ( Princeton ) and Paul Chaikin (NYU) to develop a photonic quasicrystal for efficiently trapping and manipulating light in selected wavebands. He has written over 200 papers, has edited 4 books, and has several U.S. patents.

 

	Prof. Neil Geoffrey Turok Neil Geoffrey Turok was born in 1958 in Johannesburg , South Africa , the son of Mary and Ben Turok activists in the anti-apartheid movement and the African National Congress.. Currently he holds the Chair of Mathematical Physics at Cambridge University . After graduating from Churchill College , Cambridge , Neil gained his doctorate from Imperial College , London , under the supervision of Professor David Olive, one of the inventors of superstring theory. After a postdoctoral post at Santa Barbara , he was an associate scientist at Fermilab, Chicago. In 1992 he was awarded the James Clerk Maxwell medal of the Institute of Physics for his contributions to theoretical physics. In 1994 he was appointed Professor of Physics at Princeton University , and before moving to his current position in Cambridge in 1997. Turok has worked in a number of areas of mathematical physics and early universe physics, focusing on observational tests of fundamental physics in cosmology. In the early 90's his group showed how the polarisation and temperature anisotropies of the cosmic background radiation [CMB] would be correlated, a prediction which has been confirmed in detail by recent precision measurements by the WMAP satellite. They also developed a key test for the presence of a cosmological constant, also recently confirmed. Turok and collaborators developed the theory of open inflation. With Stepehen Hawking, he later developed the so-called Hawking-Turok instanton solutions, which can describe the birth of an inflationary universe.. In 2003, Professor Turok founded the African Institute for Mathematical Sciences in Muizenberg, a postgraduate educational centre supporting the development of mathematics and science across the African continent. He was awarded the 2008 TED Prize for his work in mathematical physics and his work through the Institute in Muizenberg.

Our story begins in March 1980, Paul Steinhardt then being a Junior Fellow in the Society of Fellows, Harvard University . He comes to know that one Dr. Alan Guth of Stanford is going to deliver a seminar on the Inflationary Universe, and decides to attend. He goes because this is a weekly seminar where one often hears bold ideas discussed by people working in frontier areas. The seminars focussed on topics in particle physics, the area in which Paul was immersed in at that time; a talk on cosmology in the Harvard Seminar was somewhat unusual and Paul decided to give it a try. And when he went there, he was happy to see all the local stars including many Nobel Prize winners and his own Ph.D thesis advisor were there. So far so good.

	Dr. Alan Guth

To continue, Guth gave his talk. It was very unusual – not surprising since the topic, cosmology was something only a few bothered about. Paul recalls, “I was stupefied. Guth had pieced together concepts from three disparate-disciplines of physics – grand unification theories [which try to unify the electromagnetic, weak and strong forces under one umbrella], general relativity and thermodynamics ( the study of how systems change with temperature) all areas that I enjoyed and knew well, and he had applied them to a subject I knew nothing about, cosmology, with revolutionary effect.”

Even as Paul was beginning to be thrilled, something happened; Paul again: “Then came the crash…..[Guth then] explained why the bold and beautiful inflationary idea was doomed to dismal failure. The very mechanism that solved the cosmological problems made it impossible for the rapid explosion to end. Inflation, once begun, would continue for ever!”

Reading this, you might wonder why I did not mention anything about this in the earlier issue wherein I introduced you to the idea of cosmic inflation. There I told you that the incredible inflation was shut off pretty quickly. I was telling you there about something what emerged after the initial bug had been fixed.

Back to Paul: “I simply could not believe that such a beautiful idea could fail so catastrophically. Immediately after the lecture, I tried to see if I could find a flaw by examining each step of the analysis and by checking it using other methods. As I became more frustrated, I became more excited. I realized that whether inflation could be saved or not, there were more important problems to be solved. If inflation failed, it only meant that a new solution to the cosmological problems had to be found. I figured that I would divert my attention from my ongoing research for a month or two to see if I could concoct a solution; then, after this brief sojourn into cosmology, I would return to my research on quantum field theory. Needless to say, I was naïve; twenty-six years later, I am still working on cosmology.”

Well, that tells you something about the compelling magnetism of this subject, does it not?! Let me get on with the story, Paul’s side that is. He was now hooked on cosmology, and struggling to fix the problems that existed then in the inflation picture. Slowly, he drifted towards making a place for quantum fluctuations. As you might recall, in an earlier issue, I had pointed out how Linde had independently incorporated this feature and finally came to a model of his own; what we now learn is that Paul Steinhardt also was drifting in the same direction, along with a few associates of course. On the way, there were moments of doubt; as Paul recalls, “Turner [a collaborator at that time] and I realised that the quantum fluctuations could spell triumph or tragedy for inflation.”

Dr. Stephen Hawking authored the now famous book: 'A Brief History of Time'

Many were on the same track and, as Paul notes, by the summer of 1982, it had become a red-hot topic. Around that time, Stephen Hawking in Cambridge was organising a workshop, intended to bring together some of the active workers, so that ideas could be exchanged and the fog cleared to some extent, if possible. Over to Paul now, for his recall of the workshop: “So, the workshop began with three draft papers with three different answers, and four different mathematical approaches, some spelled out and some not.

Despite the chaos it caused at the outset of the meeting, having different approaches proved to be important for cracking the problem, because the calculation was subtle and complex mistakes were easy to make no matter which method was used. Also, each method was approximate, to some degree, invoking various simplifications and assumptions that made the calculations tractable. It was essential to have alternative methods to see if the different approximations gave answers.”

May be I should clarify one point here. One thing the inflation picture had to make room for was for galaxies to be born, in billions really! You might ask, “what’s the problem?” Well, let us say the inflation fattened the Baby Universe enormously and then ended. Fine. However, if at the end of the inflation, the resulting Universe is very smooth, then there would be no chance for galaxies to nucleate and grow; there must be some tiny fluctuations in density at the end of the inflation so that in some regions of space at least, there are pockets of higher density that form the seeds from which galaxies could sprout and grow.

At the end of the workshop organised by Hawkins, the models did allow room for seeds for galaxies, that is to say, the Universe which emerged after inflation did have density fluctuations that allowed galaxies to form and grow. But there was a problem and a big one too – the fluctuations in density that the various models offered were far too big for comfort. The prediction proved to be wrong soon after results from the satellite WMAP started becoming available. If you recall, and I had described earlier what this satellite and the later one COBE did, the satellites measured temperature fluctuations in the background cosmic radiation. While the theory forecast fluctuations of several degrees, experiments reported something a thousand times or more smaller. Clearly, that was a big set back.

	Aspen Institute for Theoretical Physics (AITP) Aspen, Colorado, nestled in the Rocky Mountains   A digression on Aspen is very essential to highlight how much scientific research has changed from the highly individual enterprise it used to be till the end of the nineteenth century. Since then, the emergence of rapid transport, advanced communication facilities, and of course generous funding by enlightened agencies, have together promoted retreats, that earlier were the privilege of philosophers and writers. Aspen is a scenic spot nestling in the American Rockies in State of Colorado . For long, it was a much-sought-after hide out for city folk wanting to escape the rate race. In the post-war years, it also became a retreat for scholars who could withdraw there to reflect deeply on various scholarly matters. And, out of this practice was born the Aspen Institute for Humanistic Studies. In 1961, two physicists approached The Aspen Institute for Humanistic Studies with an intriguing idea. The scientists, George Stranahan of the Carnegie Institute of Technology and Michael Cohen of the University of Pennsylvania , proposed a unique sort of research center where theoretical physicists might gather in the summer. It would be an unstructured environment, free from distractions, where physicists could work unfettered by their normal responsibilities. Dr. Michael Cohen The idea was warmly received and soon it was agreed that as a part of the Aspen Institute, there would be a new division called the Aspen Institute for Theoretical Physics [AITP] would be the newest division of the Aspen Institute. The Aspen Institute would set aside part of its Aspen Meadows campus for use by the physicists. In turn, the physicists would be responsible for raising funds for their own buildings and operations and would depend on their own institutions or research grants for their summer salaries and living expenses. By 1962, the AITP was functional and by 1968, it had become a great success, gaining world-wide recognition. The Aspen Centre for Physics is specifically designed to promote innovative research and collaboration. Aspen is a chic little town nestled high up in the Rocky Mountain . The Centre for Physics provides a relaxed atmosphere where people could work, talk, and just hang out. There are of course formal presentations but most of the work is actually done during informal sessions, long walks and even picnics. The usual rat-race atmosphere is absent, and with people with diverse interests and backgrounds converging, many novel ideas are born and new collaborations are forged. At lunch time, everyone joined in volleyball games, but even here, people on the sidelines waiting for their turn to play discussed physics. It all might sound like a holiday camp but but behind the apparent relaxed atmosphere, the focus on physics is intense. The Aspen Institute   Today, along with the Aspen Institute, the Music Associates of Aspen and the International Design Conference in. Aspen, it is part of the Aspen Meadows Campus, which exists as a unique and special community of artists, scholars and scientists. Here, the essence of the work lies in thought and communication. Often, it takes place on the benches under the trees, in the halls between the offices, on the trails behind the campus or hiking in the surrounding mountains. There are few distractions or responsibilities, few rules or demands. Physicists work at their own speeds and in their own ways: alone or together, at the desk, at the blackboard or in a chair on the lawn. Frequently, a casual, spontaneous discussion gives rise to a new collaboration. Activities outside the Center are encouraged. Dozens of bicycles fill the racks outside the buildings. Topographical maps cover the lobby walls suggesting hiking locations. The shady streets of Aspen 's West End invite long walks. The musicians in the nearby Music Festival Tent fill the air with music. And as the founders anticipated, even while participating in these activities, the physicists continue to exchange ideas, returning refreshed, and eager to immerse themselves once again in their individual research subjects. Physicists who come to Aspen in the summer often bring their families. Evening picnics at the Center have become a tradition, encouraging ties that are personal as well as professional. In a few cases, children who came to the Center with their parents are now young physicists attending summer sessions in their own right. The international participants come from universities, private research laboratories and government laboratories and they include young scientists as well as those who are better established. While participants must provide their own salaries, the Center does offer a "dislocation" allowance based upon need to help defray the cost of housing. All of the housing is provided through the Center. The Physics Center makes a special effort to bring distinguished physicists from abroad by paying part of the cost of their foreign travel. The Center has also hosted several joint U.S./U.S.S.R. cooperative programs. Physicists have found the Aspen-sojourn a real God-send. For many, the demands of teaching and administration often interfered with research and scientific thought. For these and many such others, who had an urgent need to catch up, Aspen was where they could re-charge their batteries, because, among other things, the wonderful setting offered an excellent chance for quiet reflection, and gearing up to new challenges.

In the summer of 1983, many theorists gathered at the resort station Aspen in Colorado to ponder about the whole issue. Paul goes there and along the side, he has another job – to conduct a Ph.D viva voce examination of a candidate named Neil Turok of Imperial College , London , whose thesis had been sent earlier to Paul for scrutiny. And this is where Neil enters the picture and let us now turn to his part of the story. But before that, a few parting words from Paul: “Because both Neil and his adviser, David Olive, were attending the Aspen workshop, Neil’s oral presentation was arranged to take place at the Aspen Institute on some afternoon during our time there – a fanciful location for a thesis defence, to be sure.

Although Neil’s thesis was mostly mathematical in nature, with only one section somewhat related to cosmology, I decided to focus on that portion during the oral presentation. I wanted to test whether he had any serious interest in this area. I was very impressed by the outcome. Although he was obviously new to cosmology, Neil displayed an unusual combination of technical prowess, creativity, and self-confidence. I passed him, of course. But in addition to that, I made a mental note to follow this talented fellow’s career and look for an opportunity to collaborate with him in the future.” That had to wait for many years though.

Cosmic Strings: one theory of spaghetti-like strands that stretched out to form our universe

We now turn to Neil Turok whose love affair with physics began in 1980 during the final year of his undergraduate studies in Cambridge University . At that time, he attended a lecture given by Stephen Hawking; the title was provocative: Is the End in sight for Physics? Basically, Hawking was thinking aloud whether a Theory of Everything was finally in sight. Neil found that talk so stimulating that he decided that he would plunge into Theoretical Physics and immediately went around looking for a suitable thesis adviser. He found one in David Olive, a brilliant and original mathematical physicist.

When the time came, Olive set Neil Turok a real tough problem to solve, very mathematical in character. At this point, let us hear Neil himself: “Near the end of the project, concerned that my research was too formal and abstract to connect with the real world, I wandered into the office of one of my professors, Tom Kibble, to express my frustration. Kibble is one of the United Kingdom ’s most distinguished theoretical physicists.…

A few years earlier, Kibble had realized that many unified theories automatically predicted that objects called cosmicstrings would form in the extreme conditions of the hot early universe. Cosmic strings are thin strands of concentrated energy that crisscross space in a spaghetti-like network and progressively straighten themselves out as the universe expands.” There were even suggestions that there could be some connection between cosmic strings and galaxy formation. Neil again: “Intrigued by the potentially spectacular link between fundamental physics and cosmology, I started working with Kibble on cosmic strings while finishing my main Ph.D project.”

So that was how Neil Turok started working on topics that bridged particle physics and cosmology, involving strings in particular. Before I proceed further, I cannot resist the temptation to make a comment or two about the father of Tom Kibble. The reason is simply this; Tom’s father, Dr. W.F. Kibble was a Professor of Mathematics in the college where I had studied, the Madras Christian College in Madras – that was in the late forties and early fifties. I never attended any classes taken by Dr. Kibble but he was very well known as an extremely absent-minded professor. And sure enough, there were many Kibble jokes, all harmless of course, poking mild fun at this very fine and kindly gentleman. One of these is the following: There used to be right in front of the college building a big sun-dial – a clock where you read the time via the shadow cast by the sun on the specially made dial. The story goes that one evening, Dr. Kibble returning from a long walk wanted to know what time it was. It was dark and he had no watch. But he had a torch and he then went to the sundial and shone the torch on it to find out the time! Bit unfair but then, as always, I suppose boys would be boys. By the way, I wonder whether son Tom ever spent time in the campus with his father. Probably he went to school in England but I am sure he must have come now and then to India to be with his parents.

Anyway, getting on with our main story, we now cut to Aspen where Neil went with his adviser and there faced the viva by Paul, his future collaborator. Back to Neil: “After my thesis defence in Aspen , there was champagne all around. As all of us celebrated, we speculated about where the new field of particle cosmology might lead. The growing problems in the theories of inflation and grand unification [of all the fundamental forces in physics] were worrisome, but the mood was nevertheless sanguine. Many anticipated that the setbacks would be minor and that particle physicists, cosmologists, and astronomers would henceforth work together in a powerful, combined discipline that would advance our knowledge of, simultaneously, the very large and the very small.”

Things did not quite turn out that way. Not only did the anticipated collaboration between Paul and Neil not form immediately, but, even more generally, particle physicists and cosmologists went their own ways. We cut now to 1996 when Neil, after a spell in America , was now back in Cambridge . The big interest was on what kind of temperature fluctuations were required in the early universe to trigger galaxy formation. Over now to Neil to hear what happened then:

	Dr. Valery Rubakov

“It was with a very open mind that I decided to propose a scientific program at the Isaac Newton Institute for Mathematical Sciences in Cambridge devoted to cutting-edge issues in cosmology. …… To develop the proposal I needed some co-organizers, and it did not take me long to decide who the ideal choices would be.” It would be Paul Steinhardt in America and Valery Rubakov, of the Institute for Nuclear Research in Moscow . Neil again: “To my delight, both Paul and Valery accepted immediately. We decided to kick off the program with two conferences: one on the latest developments on the observational side and one on new theoretical ideas....

In the final month as the [second] meeting approached, more and more people signed up to attend. The meeting was a huge success …………… The Isaac Newton Institute meeting was above all, a vital stimulus to our own research. It convinced us that, finally, string theory and super-gravity has something really interesting and new to say about the cosmos. After more than a decade, Paul and I had finally converged on a project we wanted to pursue together.”

What was that? Well, the short answer to that is: Giving the Big Bang a new and origina twist! That is exciting, is it not? What exactly was that new twist? Ah, for that you would have to wait till the next issue!

Meanwhile, I wish to make just two comments here. The first is that what we get as science news in books, magazines, radio and TV is like a finished movie; we get to see and hear only about the end-result. In the present instalment, I have made a deliberate attempt to give you a glimpse of what goes on behind the scenes, how scientists too stumble, grope for, fail and try once more, and so on in their quest to unravel the mysteries of Nature. Also, how they are obsessed with the quest. That is why a famous Indian scientist Sir C. V. Raman [about whom Swami often speaks to students] once said, “Science is a very jealous mistress,” meaning she does not allow her devotees much time to get involved in other things. When two scientists who are intensely engaged in research meet, they start talking shop before even saying hello. And if they happen to be competitors, they carefully guard all information about what they are doing, even as the other person is desperately engaged in a fishing expedition!

All this is fascinating colour and background no doubt but one reason why I am making a special point about including this “local flavour” if I might call it that is to stress that when the chips are down, all so-called great people, be they artists, musicians, writers, sportspersons, scientists, and so on, are as much susceptible to human weaknesses such as rivalry, jealousy, and so on. That said, it is an empirical fact that a large percentage of scientists who are properly trained, do try to be as objective as possible while making their judgement – that is their nature; this is just like doctors by and large being instinctively compassionate.

Now what is the point I am trying to make with all this blah? In fact, is there any? You bet there is! And that is the following: Science today has become too powerful; which means its management and steering must be overseen by society as a whole so that science and technology are not hijacked by unscrupulous interests whose only goal is to make a fast buck. If you think about it for a while, you would quickly realise how important this responsibility is.

How is society to make sure that it acts as a good watch-dog? By itself being solidly committed to morals, to Sathya and Dharma. And when would that happen? When each and every individual human being himself or herself as the case may be, becomes a devotee of Sathya and Dharma. So, if we call ourselves devotees of Swami, we had better start with a simple self-check: “I call myself a devotee of Swami but am I also a real devotee of Sathya, Dharma, Prema, Shanti and Ahimsa?” Let our Conscience speak and give the answer; don’t let ego reply!

So long, and take care! May all be well with you in the meanwhile!! Jai Sai Ram.

 

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