Hilbert's Pace
The Quest for Truth, Beauty, Serenity and Insight
in Theoretical Physics
Hilbert's Pace
The Quest for Truth, Beauty, Serenity and Insight
in Theoretical Physics
“The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful. If nature were not beautiful, it would not be worth knowing, and if nature were not worth knowing, life would not be worth living. Of course I do not here speak of that beauty that strikes the senses, the beauty of qualities and appearances; not that I undervalue such beauty, far from it, but it has nothing to do with science; I mean that profounder beauty which comes from the harmonious order of the parts, and which a pure intelligence can grasp". - Henri Poincare
“In my entire scientific life, extending over forty-five years, the most shattering experience has been the realization that an exact solution of Einstein’s equations of general relativity, discovered by the New Zealand mathematician, Roy Kerr, provides the absolutely exact representation of untold numbers of massive black holes that populate the universe. This shuddering before the beautiful,” this incredible fact that a discovery motivated by a search after the beautiful in mathematics should find its exact replica in Nature, persuades me to say that beauty is that to which the human mind responds at its deepest and most profound." -Subrahmanyan Chandrasekhar
Mathematical Reality denotes the world of mathematical objects, relations between them, the constructions, logical conclusions, the methodology and all that is succintly captured by the splendid edifice of Theoretical Physics. It differs subtly from Theoretical Physics proper in that it gives greater significance to the mathematical aspects of theoretical physics though not getting too much into purely mathematical methods as in strict Mathematical Physics.
The quest for the laws of Nature is perhaps the most enthralling of all quests and symbolizes the great Western question of all time, "What is it?" complementing the great Eastern question of all time, "Who am I?". It is immediately clear that "What is it?" refers to objective reality. Now, objective reality appears is perceived by the brain as a certain pattern and presented to the mind as a percept which, in turn, represents it to the intelligence as a concept. In this transit from the brain to the mind and intelligence, the percept itself metamorphoses into a symbol far removed from primitive experience and that means, from ordinary language. Thence arises a world of symbolic objects, forms and relations that endow the world of percepts with meaning. It is this infusing of meaning into the primitive world of percepts that is the real key to an appreciation of mathematics. Ever since Plato put forth his "edios," as being prior to the objective world, there has been a debate among mathematicians and natural philosophers as to the priority of these worlds. Nevertheless, it is undeniable that mathematics as applied to physics is responsible for the profoundly beautiful domain and field of theoretical physics that represents human creativity at its deepest and highest.
Dr. B S Ramachandra's own life and work represents his magnificent obsession with theoretical physics and his deep purpose to rekindle and revitalize the education of bright young minds with the keen insights he has gained by dedication to a life centred entirely around learning, research and scholarship. A brilliant student who failed continually at school during his 8th, 9th and 10th grades and was almost lost to the academic world, then jumping back into the top of the ladder in his academics during his 11th and 12th grades, and after that, joining an engineering college to do mechanical engineering, getting interested in theoretical physics and being engrossed in it to the near exclusion of everything else, failing formally in his engineering college due to his preoccupation with theoretical physics and mathematics, coming at the top of the Ph. D entrance examination in India, joining the Indian Institute of Astrophysics, working on Classical General Relativity and Black Hole Physics for his doctoral thesis and in actuality, getting deeply involved in Loop Quantum Gravity, giving up a prestigious post-doctoral cum faculty position offer from IUCAA, India, a possibility from the University of Paris, France, the possibility of joining Penn State, USA, to pursue Quantum Gravity and instead, to work for the cause of educational reconstruction in India, establishing the Centre for Fundamental Research and Creative Education, Bangalore, India along with Pratiti B R and revolutionizing the education of purpose-driven young minds to a phenomenal degree...and leveraging hundreds of bright young minds into extraordinary levels of learning and research.
Below is sketched a conversation of Karthik Bharadwaj with Dr. B S Ramachandra about the meaning and purpose of his website "Mathematical Reality."
KB: I think it is best to start with the name "Mathematical Reality." What would you say is the reason for it?
Dr. BSR: I was looking for a suitable name to capture the fact that I was going to write about truth and beauty in theoretical physics. During the earlier years when I was doing my Ph. D in theoretical physics, I was motivated more by the sense of mathematical beauty than the truth a particular theory contained or gave rise to. It is not that I was not concerned with "truth." In fact, that was the main reason for my choosing theoretical physics over pure mathematics. I say pure mathematics in a quite serious sense, for I had been involved in studying pure mathematics for nearly four years exclusively, I mean, to the near exclusion of theoretical physics, two years before I began my Ph. D program.
I worked through several volumes of J Dieudonne’s “Treatise on Analysis,” and many of Serge Lang’s books and of course, Abraham and Marsden’s “Foundations of Mechanics,” to name a few. But after that brief period of immersion in pure mathematics, I returned to theoretical physics being forcefully carried away by a sense of profound mathematical beauty. So when a year ago, when I thought of writing about my insights and perspectives, I thought of fusing truth and beauty with serenity and insight and naturally the term "Hilbert's Pace" popped up in my mind.
KB: Now that you mentioned it, could you go over a little about how you came to theoretical physics? I think this will give a much needed perspective into the term, "quest," that you talk of quite often.
Dr. BSR: Sure. I came across the term "theoretical physics," apparently by accident but really by a half-conscious stumbling upon it led by my deep quest. As many may not be aware, till my 7th grade, I was a conventionally bright student, at the top of my class. But during my 8th and 9th grades, I had an appalling fall in academics and I plummeted to the bottom of the academic ladder, in fact securing the 33rd rank in my class and dubbed the worst student in the school! In my 10th grade, however, I realized the danger I had fallen into, of the abyss I was heading into, from which there could be no climbing back. I put in a prodigious amount of effort and jumped back onto the higher rungs of the academic ladder.
So after my 12th grade, I found myself joining an engineering college for the Bachelors degree program in Mechanical Engineering. Now there were around five months before the engineering college started. I had gotten interested in physics and mathematics in my 11th and 12th grades and so I continued to study mathematics and physics independently. I went to bookshops and got hold of advanced books on mathematics and physics. I think it was during this period that the word "theoretical physics," struck me. I think it was in the Feynman Lectures on Physics. But initially I did not give that much importance to it, though it no doubt intrigued me.
After the five month period was over, I was filled with a profound sense of quest and eagerly went to the engineering college, more so at the prospect of getting access to the library than for the classes. You must remember that in those pre-internet times, libraries were the only source of books, especially on advanced mathematics and physics. So I went to the college library and looked around. Two books caught my attention. One was a beautiful silver colored book by Morse and Feshbach, "Methods of Theoretical Physics." The other was by Bjorken and Drell, "Relativistic Quantum Mechanics." That was my first conscious encounter with theoretical physics. I plunged into Morse and Feshbach's book and in around two month's time, was into the thick of it. By the time I was through reading the book, I knew that I was not born to be a mechanical engineer but a theoretical physicist.
KB: When you say "I was not born to be a mechanical engineer but a theoretical physicist," are you saying that you were aware that you wanted to be a scientist right from your early years?
Dr. BSR: In a sense, yes, though the word scientist had not particularly drawn my attention. In India, when people talk of a scientist, they mean more in the sense of technology, of invention or innovation. They have the idea of Edison who was an inventor, to represent the image of a scientist. I have no problem with that except that I think it distorts the meaning of the term scientist. A scientist is one who seeks the unknown and is more into discovery than invention. Well, I was more interested in discovery, though I did engage myself in many a hands-on tinkering with gadgets and minor inventions, that most kids are into.But I was more interested in the philosophical quest for what is behind phenomena and did not then realize that being a scientist could lead to that. But yes, even then, I was aware that I was going to be someone who discovered things.
KB: It was during your engineering program that you actually got into theoretical physics. It would be really interesting to know more about that, and keeping the theme of the website, “Hilbert's Pace,” you could talk about your pursuit of mathematical beauty in theoretical physics.
Dr.BSR: I think it is quite natural for me to be motivated by mathematical beauty because of the unconventional and novel way I entered theoretical physics. Normally one would do so starting out with Classical Mechanics, Classical Electrodynamics, Quantum Mechanics along with Mathematical Methods. I, on the contrary, started out with General Relativity!
KB: General Relativity? How could you manage that? Without the background that the branches you mentioned, especially as General Relativity is one of the more difficult branches of theoretical physics and is not accessible before the doctoral level.
Dr. BSR: I agree, it is very unusual and in my case it is one of the power of ignorance triumphing over knowledge. With my present understanding of cognitive neuroscience and positive psychology, I would say it was a case of me not having picked up “learned helplessness,” that most students do. I mean, I was not “taught” that it was not possible to do fields like General Relativity and so I went ahead and did it. The how does not matter, as once you have a sufficiently strong “why,” the how gets figured out by the subconscious. But I think I am digressing a bit too much from our main theme.
Let me get back to that, of mathematical reality. So, having started out with General Relativity, it was natural for me to be struck by its profound mathematical beauty of what Hawking and Israel capture so beautifully in the book they are editors of, “General Relativity, An Einstein Centenary Survey,”
“No-one can recall without a thrill his first encounter with this Carollian world where space is curved, time a fourth dimension and honest witnesses blithely disagree on the most elementary questions of what happened when and where.”
I had first came across the term “tensors,” in the book by Jeremy Bernstein, “Einstein,” that I read in my 7th grade, and later, during the five month period before my engineering, I read the absolutely wonderful book, “Space, Time, Gravitation,” by Minrosky et al, a Mir Publishers book. That book really gave a glimpse and opened my eyes to the magical beauty of not only tensors but of Elie Cartan’s exterior calculus, Riemannian Geometry, Finsler spaces, Weyl’s gauge invariant geometry, Kaluza-Klein theory and so on. But this was at a semi-technical level. I soon got hold of the beautiful Landau and Lifshitz course of theoretical physics, Vols 1 and 2, “Mechanics” and “The Classical Theory of Fields,” respectively, and that was the beginning of my serious learning in General Relativity. I followed this up with the older book by Peter Bergmann, “Relativity,” and then another older book by C Moller, “General Relativity.” These were the only books I could get hold of during those times when libraries and that also, the libraries at the research institutes, were the only source of such books.
Around this time, things happened quite fast and cutting a long and involved story short, I began to meet Prof. J Pasupathy, at the Centre for Theoretical Studies, Indian Institute of Science, Bangalore, India, from time to time. He gave me Steven Weinberg’s book, “General Relativity,” that I mastered in one month’s time and moved on to the bewitchingly beautiful book by Hawking and Ellis, “The Large Scale Structure fo Spacetime,” and of course, Misner, Thorne, Wheeler’s “Gravitation.” That was the point of no return for me. I could never, ever live an ordinary life. It lifted me to heights I could not imagine. I was lost in ecstasy for weeks and months working through that book. It led me to master Topology and Differential Geometry from the books by J Kelly, “General Topology,” Hocking and Young, “Topology,” Sigurdur Helgason, “Differential Geometry, Lie Groups and Symmetric Spaces,” and Kobayashi and Nomizu, “Foundations of Differential Geometry,” Vols 1 and 2, V I Arnold’s “Mathematical Methods of Classical Mechanics,” T J Willmore’s “Total Curvature in Riemannian Geometry,” and a host of other wonderful books.
And in all these, the most beautiful experience I had was mastering Elie Cartan’s calculus of differential forms and working out the Schwarzschild and Kerr solutions of the Einstein field equations, maximally symmetric spaces, the Penrose 2-spinor formalism and classification of the gravitational field, Twistor cohomology etc. In a sense, mathematical beauty came to me most evocatively in the works of Elie Cartan. Nothing else quite equals that and even today, I am into pursuing the deeper ramifications of Elie Cartan’s work through the framework of multisymplectic geometry, especially from the works of G Sardanashvily and his collaborators, Jerrold E Marsden, Mark Gotay (The GIMMSY articles) and of course, Robert Hermann’s wonderful books on Cartan’s work.
KB: That really was a sweeping view of your entry into theoretical physics. I have myself mastered Elie Cartan’s methods and cannot but agree on what you said. In my own work, I am applying symplectic geometry to quantum mechanics and truly, the mathematical beauty is really striking.
Dr. BSR: And added to the pursuit of Elie Cartan’s methods, I soon encountered Gauge theories…and…my breath almost fails to utter this…it was the most enthralling, magical experience of my life…to realise that the structures behind Gauge theories and Fibre bundles were the same. I can only describe this by quoting Keats in his Endymion,
"Wherein lies happiness? In that which becksOur ready minds to fellowship divine,A fellowship with essence; till we shine,Full alchemiz’d, and free of space."
I lost sense of day and night in working through these realisations and understanding upon understanding crowded upon me. I worked on theoretical physics so much that often I was awake for two days at a stretch and slept only the next day, missing my classes at the engineering college. I would get up in the midst of a dream and rapidly transcribe my insights that I had received in a metaphorical form, into words. I could no longer identify with what I had been just a few years earlier. I was a transformed person, the quest had captured me completely and I felt truly blessed, for want of a better phrase, to have been vouchsafed this path into theoretical physics. Theoretical Physics, to me, therefore, is the deepest calling of the soul, the hero’s journey, an adventure to the promised land. Shelly’s Alastor or Spirit of Solitude, best captures my feelings, in the infancy of my entry into the world of theoretical physics.
"By solemn vision, and bright silver dream,His infancy was nurtured. Every sightAnd sound from the vast earth and ambient air,Sent to his heart its choicest impulses.The fountains of divine philosophyFled not his thirsting lips, and all of great,Or good, or lovely, which the sacred pastIn truth or fable consecrates, he feltAnd knew."
KB: The way you say it, I feel the stirrings of the spirit. Yes, it is so true that as one goes deeper and deeper into the heart of theoretical physics, it becomes impossible to turn back to the ordinary life and I think that is the reason you say it is the hero’s journey. For, as I recall Joseph Campbell’s book, “The Hero with the Thousand Faces,” the hero leaves the ordinary world and embarks on his journey. And as he proceeds, he hesitates and many a time, feels like giving up. And there intervenes a stage after which he knows that the return to the ordinary world before completing the hero’s journey is impossible.
Dr. BSR: Yes, you put it accurately. And in me that departure from the ordinary world and into the world of theoretical physics was also accompanied with a growing sense of what I can best call, austerity, a sense of purity, as if all my physical, emotional, mental and psychic energies were getting concentrated towards the quest and providing the rocket-propulsion necessary to escape the pull of the ordinary world.
To me, theoretical physics symbolised a mystical journey into the realm of pure thought and spirit and I felt the deep transmutation taking place in me day and night. The mathematical beauty soon fused into truth and then the sense of immaculate serenity settled upon me making my quest for the laws of Nature utterly intrinsic. All these feelings began to bring forth insights too numerous to express and too profound to communicate. That is why, I still have notebooks and sheets filled with my writings and papers, finished and unfinished, that I have chosen to just let them stack up and stand by. What you are going to see in the website, “Mathematical Reality,” is just drawn forth partly from these insights.
KB: I think it would clarify a lot if you could outline in your own words the famous CFRCE Theoretical & Mathematical Paradigm that was an outgrowth of your vision during your engineering times.
Dr. BSR: Sure, and for that I would have to talk something about the Beginner’s Brain-Mind. The beginner’s brain-mind comes with unlimited possibilities for learning teeming as it is with potential skills that naturally require a worthy challenge. Lacking this challenge, the beginner becomes disillusioned and the psychic energies get scattered in fruitless efforts. It is, therefore, indispensable to provide a roadmap that accommodates the tremendous firing of the BDNF.
As a young beginner during the heyday of my own strivings in theoretical physics I myself faced this necessity of providing myself a challenge that I could devote all my energies to. As I could not find any guidance from wither the literature nor from the community of researchers, I tried several paths that appealed too me. For a time I even went over entirely into Pure Mathematics thinking that it would best provide the resources I was looking for to take on Theoretical Physics in earnest. After three to four years of Pure Mathematics, I came to agree with what Einstein writes in his autobiographical notes,
“I saw that mathematics was split up into numerous specialties, each of which could easily absorb the short lifetime granted to us. Consequently, I saw myself in the position of Buridan’s ass, unable to decide upon any bundle of hay.”
Thus disillusioned though not disappointed, by Pure Mathematics I returned to Theoretical Physics. But my immersion in mathematics was not a fruitless exercise. For, when I returned to physics, I found that an entirely new perspective had emerged. Suddenly, theoretical physics seemed to be running through several threads all starting from the Calculus of Variations. I looked to formulate a unifying scheme that would give me the organising principles for my research. As I began to sketch it out, the picture formed on the canvas of my mind and emerged into a full-blown roadmap. So enthralled I was as I put it down on paper that I could not sleep well for a few weeks and lost my appetite. I moved about in a daze and in the classes at my engineering college, I sat like a deaf and dumb person absorbed in my own world and with my eyes abstracted on an inner vision.
I spend the next few months in the library at the Indian Institute of Science and the TIFR Centre that was in its campus, putting together source books and references and hunting down review articles from Physics Reports, Rivista del Nuovo Cimento, Reviews of Modern Physics, Journal of Mathematical Physics, and several other journals, proceedings of summer schools and conferences etc. And next, it was not enough to list these, I needed to get hold of them in order not to interrupt my studies. Over the ensuing months I managed to get hold of all these and those that were not available I procured them by writing directly to the mathematicians and physicists.
One of the most memorable of the articles I received was from Marcel Berger, from Paris, “Riemannian Geometry During the Second Half of the Twentieth Century.” After gathering all these, rather as I was gathering them, I embarked on my grand vision of mastering all the essential branches of Theoretical and Mathematical Physics in a unified manner, mapping out the varied interconnections, inter-dependencies and logical independence of the topics. The more I worked out these sources, the more my notes grew. My engineering studies dwindled away and I began to play truant with my college.
This pattern carried over through my entry into the Indian Institute of Astrophysics and though my formal thesis work was in Classical General Relativity and Black Holes, I continued to work away on my vision towards Loop Quantum Gravity. I soon saw that the other students began to notice the strange things I was involved in and to prevent interruption I rapidly switched to night mode. I appeared at the institute later and later in the day till there came a stage when I reached the institute as others were leaving for the day. I would go to the library and sit through the whole night with my pile of books and papers that I used to carry in my trekking backpack. Those times I had my motorcycle to the front of which I had devised a special mechanism to attach and tie my backpack as it was generally quite heavy at any given time containing over twenty to twenty five books and papers.
My roadmap also became extremely clear and concrete to me around this time. Here is an updated version as we use it at CFRCE.
KB: You have chosen certain key topics to portray as in the boxes with the green backgrounds?
Dr. BSR: Yes, in short, what I call the Klein-Cartan paradigm, Loop Quantum Gravity, Shape Dynamics, Geometric Mechanics, Geometric Quantum Mechanics, Geometric Quantization, Black Hole Physics and Foundations of Quantum Mechanics. I could have added Constrained Quantization, Multisymplectic Geometry, the Geometric approach to Hamilton-Jacobi theory, Clifford Calculus, Spin Geometry and Index Theory. But perhaps after we first get this thing going.
KB: How about giving an idea of the first topic from the point of view of the theme of this website?
Dr. BSR: Sure, let’s take the first, “The Klein-Cartan paradigm.” I mean by this a modern version of Felix Klein’s Erlangen program combined with Elie Cartan’s profound generalisation of geometry. I had been heading towards this after reading Robert Hermann’s beautiful works on the calculus of variations, differential geometry, Cartan-Ehresmann connections, Lie theory and systems. But it was only when I read the beautiful book by Sharpe, “Differential Geometry, Cartan’s generalization of Klein’s Erlangan program,” that I coined the term Klein-Cartan paradigm. I intended to take Klein and Cartan’s approach to generalise the geometric structures used in theoretical physics, especially Hamiltonian systems, momentum maps and later, multi momentum maps. I also wanted to bring in the de Donder formalism into it. There is in fact, an elegant work along these lines, that by Neemann, Hehl, McCrea, at al, “Metric Affine Gauge Theory of Gravity.” There is also another deep article by H Kastrup, “Canonical Lagrangian Theories of Lagrangian Dynamical Systems in Physics.” There also several other articles along these lines. I wanted to bring them together in formulating the Klein-Cartan paradigm. In my notes, I have outlined the approach one could take by starting out with the rotation group and studying group extensions and cohomology, generalising them and then looking into group contractions to verify the results of the departure. There is a wonderful book by Azcarraga and Izquierdo, “Lie groups, Lie algebras, Cohomology and Some Applications in Physics,” that provides much motivation for the group theoretical constructions.
KB: Great, that gives a very good idea. You have stated succinctly the purpose of "Hilbert's Pace." So we can now refer the earnest and reader to that website to take a look into the truth, beauty, serenity and insight in theoretical physics! And anyway, we plan to keep this website continually updated, in the spirit of the “Living Reviews.”
Dr. BSR: Yes, that is so. As you suggest, we update it continually depending on fresh insights and perspectives we want to share.
KB: There is also the associated blog in which you are going to post your insights and perspectives on a more regular basis.
Dr. BSR: I would like to be doing that.