Tag Archives: unreality

Articles and Essays, Philosophy, Physics, Unpublished

The Unreal Universe — Seeing Light in Science and Spirituality

We know that our universe is a bit unreal. The stars we see in the night sky, for instance, are not really there. They may have moved or even died by the time we get to see them. This delay is due to the time it takes for light from the distant stars and galaxies to reach us. We know of this delay.

The same delay in seeing has a lesser known manifestation in the way we perceive moving objects. It distorts our perception such that something coming towards us would look as though it is coming in faster. Strange as it may sound, this effect has been observed in astrophysical studies. Some of the heavenly bodies do look as though they are moving several times the speed of light, while their “real” speed is probably a lot lower.

Now, this effect raises an interesting question–what is the “real” speed? If seeing is believing, the speed we see should be the real speed. Then again, we know of the light travel time effect. So we should correct the speed we see before believing it. What then does “seeing” mean? When we say we see something, what do we really mean?

Light in Physics

Seeing involves light, obviously. The finite speed of light influences and distorts the way we see things. This fact should hardly come as a surprise because we do know that things are not as we see them. The sun that we see is already eight minutes old by the time we see it. This delay is not a big deal; if we want to know what is going on at the sun now, all we have to do is to wait for eight minutes. We, nonetheless, have to “correct” for the distortions in our perception due to the finite speed of light before we can trust what we see.

What is surprising (and seldom highlighted) is that when it comes to sensing motion, we cannot back-calculate the same way we take out the delay in seeing the sun. If we see a celestial body moving at an improbably high speed, we cannot figure out how fast and in what direction it is “really” moving without making further assumptions. One way of handling this difficulty is to ascribe the distortions in our perception to the fundamental properties of the arena of physics — space and time. Another course of action is to accept the disconnection between our perception and the underlying “reality” and deal with it in some way.

Einstein chose the first route. In his groundbreaking paper over a hundred years ago, he introduced the special theory of relativity, in which he attributed the manifestations of the finite speed of light to the fundamental properties of space and time. One core idea in special relativity (SR) is that the notion of simultaneity needs to be redefined because it takes some time for light from an event at a distant place to reach us, and we become aware of the event. The concept of “Now” doesn’t make much sense, as we saw, when we speak of an event happening in the sun, for instance. Simultaneity is relative.

Einstein defined simultaneity using the instants in time we detect the event. Detection, as he defined it, involves a round-trip travel of light similar to Radar detection. We send out light, and look at the reflection. If the reflected light from two events reaches us at the same instant, they are simultaneous.
Another way of defining simultaneity is using sensing — we can call two events simultaneous if the light from them reaches us at the same instant. In other words, we can use the light generated by the objects under observation rather than sending light to them and looking at the reflection.

This difference may sound like a hair-splitting technicality, but it does make an enormous difference in the predictions we can make. Einstein’s choice results in a mathematical picture that has many desirable properties, thereby making further development elegant.

The other possibility has an advantage when it comes to describing objects in motion because it corresponds better with how we measure them. We don’t use Radar to see the stars in motion; we merely sense the light (or other radiation) coming from them. But this choice of using a sensory paradigm, rather than Radar-like detection, to describe the universe results in a slightly uglier mathematical picture.

The mathematical difference spawns different philosophical stances, which in turn percolate to the understanding of our physical picture of reality. As an illustration, let us look at an example from astrophysics. Suppose we observe (through a radio telescope, for instance) two objects in the sky, roughly of the same shape and properties. The only thing we know for sure is that the radio waves from two different points in the sky reach the radio telescope at the same instant in time. We can guess that the waves started their journey quite a while ago.

For symmetric objects, if we assume (as we routinely do) that the waves started the journey roughly at the same instant in time, we end up with a picture of two “real” symmetric lobes more or less the way see them.

But there is different possibility that the waves originated from the same object (which is in motion) at two different instants in time, reaching the telescope at the same instant. This possibility explains some spectral and temporal properties of such symmetric radio sources, which is what I mathematically described in a recent physics article. Now, which of these two pictures should we take as real? Two symmetric objects as we see them or one object moving in such a way as to give us that impression? Does it really matter which one is “real”? Does “real” mean anything in this context?

The philosophical stance in implied in special relativity answers this question unequivocally. There is an unambiguous physical reality from which we get the two symmetric radio sources, although it takes a bit of mathematical work to get to it. The mathematics rules out the possibility of a single object moving in such a fashion as to mimic two objects. Essentially, what we see is what is out there.

On the other hand, if we define simultaneity using concurrent arrival of light, we will be forced to admit the exact opposite. What we see is pretty far from what is out there. We will confess that we cannot unambiguously decouple the distortions due to the constraints in perception (the finite speed of light being the constraint of interest here) from what we see. There are multiple physical realities that can result in the same perceptual picture. The only philosophical stance that makes sense is the one that disconnects the sensed reality and the causes behind what is being sensed.

This disconnect is not uncommon in philosophical schools of thought. Phenomenalism, for instance, holds the view that space and time are not objective realities. They are merely the medium of our perception. All the phenomena that happen in space and time are merely bundles of our perception. In other words, space and time are cognitive constructs arising from perception. Thus, all the physical properties that we ascribe to space and time can only apply to the phenomenal reality (the reality as we sense it). The noumenal reality (which holds the physical causes of our perception), by contrast, remains beyond our cognitive reach.

The ramifications of the two different philosophical stances described above are tremendous. Since modern physics seems to embrace a non-phenomenalistic view of space and time, it finds itself at odds with that branch of philosophy. This chasm between philosophy and physics has grown to such a degree that the Nobel prize winning physicist, Steven Weinberg, wondered (in his book “Dreams of a Final Theory”) why the contribution from philosophy to physics have been so surprisingly small. It also prompts philosophers to make statements like, “Whether ‘noumenal reality causes phenomenal reality’ or whether ‘noumenal reality is independent of our sensing it’ or whether ‘we sense noumenal reality,’ the problem remains that the concept of noumenal reality is a totally redundant concept for the analysis of science.”

One, almost accidental, difficulty in redefining the effects of the finite speed of light as the properties of space and time is that any effect that we do understand gets instantly relegated to the realm of optical illusions. For instance, the eight-minute delay in seeing the sun, because we readily understand it and disassociate from our perception using simple arithmetic, is considered a mere optical illusion. However, the distortions in our perception of fast moving objects, although originating from the same source are considered a property of space and time because they are more complex.

We have to come to terms with the fact that when it comes to seeing the universe, there is no such thing as an optical illusion, which is probably what Goethe pointed out when he said, “Optical illusion is optical truth.”

The distinction (or lack thereof) between optical illusion and truth is one of the oldest debates in philosophy. After all, it is about the distinction between knowledge and reality. Knowledge is considered our view about something that, in reality, is “actually the case.” In other words, knowledge is a reflection, or a mental image of something external, as shown in the figure below.
Commonsense view of reality
In this picture, the black arrow represents the process of creating knowledge, which includes perception, cognitive activities, and the exercise of pure reason. This is the picture that physics has come to accept.
Alternate view of reality
While acknowledging that our perception may be imperfect, physics assumes that we can get closer and closer to the external reality through increasingly finer experimentation, and, more importantly, through better theorization. The Special and General Theories of Relativity are examples of brilliant applications of this view of reality where simple physical principles are relentlessly pursued using formidable machine of pure reason to their logically inevitable conclusions.

But there is another, alternative view of knowledge and reality that has been around for a long time. This is the view that regards perceived reality as an internal cognitive representation of our sensory inputs, as illustrated below.

In this view, knowledge and perceived reality are both internal cognitive constructs, although we have come to think of them as separate. What is external is not the reality as we perceive it, but an unknowable entity giving rise to the physical causes behind sensory inputs. In the illustration, the first arrow represents the process of sensing, and the second arrow represents the cognitive and logical reasoning steps. In order to apply this view of reality and knowledge, we have to guess the nature of the absolute reality, unknowable as it is. One possible candidate for the absolute reality is Newtonian mechanics, which gives a reasonable prediction for our perceived reality.

To summarize, when we try to handle the distortions due to perception, we have two options, or two possible philosophical stances. One is to accept the distortions as part of our space and time, as SR does. The other option is to assume that there is a “higher” reality distinct from our sensed reality, whose properties we can only conjecture. In other words, one option is to live with the distortion, while the other is to propose educated guesses for the higher reality. Neither of these options is particularly attractive. But the guessing path is similar to the view accepted in phenomenalism. It also leads naturally to how reality is viewed in cognitive neuroscience, which studies the biological mechanisms behind cognition.

In my view, the two options are not inherently distinct. The philosophical stance of SR can be thought of as coming from a deep understanding that space is merely a phenomenal construct. If the sense modality introduces distortions in the phenomenal picture, we may argue that one sensible way of handling it is to redefine the properties of the phenomenal reality.

Role of Light in Our Reality

From the perspective of cognitive neuroscience, everything we see, sense, feel and think is the result of the neuronal interconnections in our brain and the tiny electrical signals in them. This view must be right. What else is there? All our thoughts and worries, knowledge and beliefs, ego and reality, life and death — everything is merely neuronal firings in the one and half kilograms of gooey, grey material that we call our brain. There is nothing else. Nothing!

In fact, this view of reality in neuroscience is an exact echo of phenomenalism, which considers everything a bundle of perception or mental constructs. Space and time are also cognitive constructs in our brain, like everything else. They are mental pictures our brains concoct out of the sensory inputs that our senses receive. Generated from our sensory perception and fabricated by our cognitive process, the space-time continuum is the arena of physics. Of all our senses, sight is by far the dominant one. The sensory input to sight is light. In a space created by the brain out of the light falling on our retinas (or on the photo sensors of the Hubble telescope), is it a surprise that nothing can travel faster than light?

This philosophical stance is the basis of my book, The Unreal Universe, which explores the common threads binding physics and philosophy. Such philosophical musings usually get a bad rap from us physicists. To physicists, philosophy is an entirely different field, another silo of knowledge. We need to change this belief and appreciate the overlap among different knowledge silos. It is in this overlap that we can expect to find breakthroughs in human thought.

This philosophical grand-standing may sound presumptuous and the veiled self-admonition of physicists understandably unwelcome; but I am holding a trump card. Based on this philosophical stance, I have come up with a radically new model for two astrophysical phenomena, and published it in an article titled, “Are Radio Sources and Gamma Ray Bursts Luminal Booms?” in the well-known International Journal of Modern Physics D in June 2007. This article, which soon became one of the top accessed articles of the journal by Jan 2008, is a direct application of the view that the finite speed of light distorts the way we perceive motion. Because of these distortions, the way we see things is a far cry from the way they are.

We may be tempted to think that we can escape such perceptual constraints by using technological extensions to our senses such as radio telescopes, electron microscopes or spectroscopic speed measurements. After all, these instruments do not have “perception” per se and should be immune to the human weaknesses we suffer from. But these soulless instruments also measure our universe using information carriers limited to the speed of light. We, therefore, cannot escape the basic constraints of our perception even when we use modern instruments. In other words, the Hubble telescope may see a billion light years farther than our naked eyes, but what it sees is still a billion years older than what our eyes see.

Our reality, whether technologically enhanced or built upon direct sensory inputs, is the end result of our perceptual process. To the extent that our long range perception is based on light (and is therefore limited to its speed), we get only a distorted picture of the universe.

Light in Philosophy and Spirituality

The twist to this story of light and reality is that we seem to have known all this for a long time. Classical philosophical schools seem to have thought along lines very similar to Einstein’s thought experiment.

Once we appreciate the special place accorded to light in modern science, we have to ask ourselves how different our universe would have been in the absence of light. Of course, light is only a label we attach to a sensory experience. Therefore, to be more accurate, we have to ask a different question: if we did not have any senses that responded to what we call light, would that affect the form of the universe?

The immediate answer from any normal (that is, non-philosophical) person is that it is obvious. If everybody is blind, everybody is blind. But the existence of the universe is independent of whether we can see it or not. Is it though? What does it mean to say the universe exists if we cannot sense it? Ah… the age-old conundrum of the falling tree in a deserted forest. Remember, the universe is a cognitive construct or a mental representation of the light input to our eyes. It is not “out there,” but in the neurons of our brain, as everything else is. In the absence of light in our eyes, there is no input to be represented, ergo no universe.

If we had sensed the universe using modalities that operated at other speeds (echolocation, for instance), it is those speeds that would have figured in the fundamental properties of space and time. This is the inescapable conclusion from phenomenalism.

The role of light in creating our reality or universe is at the heart of Western religious thinking. A universe devoid of light is not simply a world where you have switched off the lights. It is indeed a universe devoid of itself, a universe that doesn’t exist. It is in this context that we have to understand the wisdom behind the statement that “the earth was without form, and void” until God caused light to be, by saying “Let there be light.”

The Quran also says, “Allah is the light of the heavens and the earth,” which is mirrored in one of the ancient Hindu writings: “Lead me from darkness to light, lead me from the unreal to the real.” The role of light in taking us from the unreal void (the nothingness) to a reality was indeed understood for a long, long time. Is it possible that the ancient saints and prophets knew things that we are only now beginning to uncover with all our supposed advances in knowledge?

I know I may be rushing in where angels fear to tread, for reinterpreting the scriptures is a dangerous game. Such foreign interpretations are seldom welcome in the theological circles. But I seek refuge in the fact that I am looking for concurrence in the metaphysical views of spiritual philosophies, without diminishing their mystical or theological value.

The parallels between the noumenal-phenomenal distinction in phenomenalism and the Brahman-Maya distinction in Advaita are hard to ignore. This time-tested wisdom on the nature of reality from the repertoire of spirituality is now reinvented in modern neuroscience, which treats reality as a cognitive representation created by the brain. The brain uses the sensory inputs, memory, consciousness, and even language as ingredients in concocting our sense of reality. This view of reality, however, is something physics is yet to come to terms with. But to the extent that its arena (space and time) is a part of reality, physics is not immune to philosophy.

As we push the boundaries of our knowledge further and further, we are beginning to discover hitherto unsuspected and often surprising interconnections between different branches of human efforts. In the final analysis, how can the diverse domains of our knowledge be independent of each other when all our knowledge resides in our brain? Knowledge is a cognitive representation of our experiences. But then, so is reality; it is a cognitive representation of our sensory inputs. It is a fallacy to think that knowledge is our internal representation of an external reality, and therefore distinct from it. Knowledge and reality are both internal cognitive constructs, although we have come to think of them as separate.

Recognizing and making use of the interconnections among the different domains of human endeavour may be the catalyst for the next breakthrough in our collective wisdom that we have been waiting for.

Philosophy, Physics

Uncertainly Principle

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The uncertainty principle is the second thing in physics that has captured the public imagination. (The first one is E=mc^2.) It says something seemingly straightforward — you can measure two complimentary properties of a system only to a certain precision. For instance, if you try to figure out where an electron is (measure its position, that is) more and more precisely, its speed becomes progressively more uncertain (or, the momentum measurement becomes imprecise).

Where does this principle come from? Before we can ask that question, we have to examine what the principle really says. Here are a few possible interpretations:

  1. Position and momentum of a particle are intrinsically interconnected. As we measure the momentum more accurately, the particle kind of “spreads out,” as George Gamow’s character, Mr. Tompkins, puts it. In other words, it is just one of those things; the way the world works.
  2. When we measure the position, we disturb the momentum. Our measurement probes are “too fat,” as it were. As we increase the position accuracy (by shining light of shorter wavelengths, for instance), we disturb the momentum more and more (because shorter wavelength light has higher energy/momentum).
  3. Closely related to this interpretation is a view that the uncertainty principle is a perceptual limit.
  4. We can also think of the uncertainly principle as a cognitive limit if we consider that a future theory might surpass such limits.

All right, the last two interpretations are my own, so we won’t discuss them in detail here.

The first view is currently popular and is related to the so-called Copenhagen interpretation of quantum mechanics. It is kind of like the closed statements of Hinduism — “Such is the nature of the Absolute,” for instance. Accurate, may be. But of little practical use. Let’s ignore it for it is not too open to discussions.

The second interpretation is generally understood as an experimental difficulty. But if the notion of the experimental setup is expanded to include the inevitable human observer, we arrive at the third view of perceptual limitation. In this view, it is actually possible to “derive” the uncertainty principle.

Let’s assume that we are using a beam of light of wavelength \lambda to observe the particle. The precision in the position we can hope to achieve is of the order of \lambda. In other words, \Delta x \approx \lambda. In quantum mechanics, the momentum of each photon in the light beam is inversely proportional to the wavelength. At least one photon is reflected by the particle so that we can see it. So, by the classical conservation law, the momentum of the particle has to change by at least \Delta p \approx constant\lambda from what it was before the measurement. Thus, through perceptual arguments, we get something similar to the Heisenberg uncertainty principle \Delta x \Delta p = constant.

We can make this argument more rigorous, and get an estimate of the value of the constant. The resolution of a microscope is given by the empirical formula 0.61\lambda/NA, where NA is the numerical aperture, which has a maximum value of one. Thus, the best spatial resolution is 0.61\lambda. Each photon in the light beam has a momentum 2\pi\hbar/\lambda, which is the uncertainty in the particle momentum. So we get \Delta x \Delta p = (0.61\lambda)(2\pi\hbar) \approx 4\hbar, approximately an order of magnitude bigger than the quantum mechanical limit. Through more rigorous statistical arguments, related to the spatial resolution and the expected momentum transferred, it may possible to derive the Heisenberg uncertainty principle through this line of reasoning.

If we consider the philosophical view that our reality is a cognitive model of our perceptual stimuli (which is the only view that makes sense to me), my fourth interpretation of the uncertainty principle being a cognitive limitation also holds a bit of water.

Reference

The latter part of this post is an excerpt from my book, The Unreal Universe.

Articles and Essays, Books, Creative, Philosophy

Zen and the Art of Motorcycle Maintenance

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Once, I had some doubts about my sanity. After all, if you find yourself questioning the realness of reality, you have to wonder — is it reality that is unreal, or your sanity?

When I shared my concerns with this philosophically inclined friend of mine, she reassured me, “Sanity is overrated.” After reading Zen and the Art of Motorcycle Maintenance, I think she was right. Perhaps she didn’t go far enough — may be insanity is way underrated.

Zen and the Art of Motorcycle Maintenance defines insanity as the process of stepping outside mythos; mythos being the sum total of our combined knowledge passed down over the generations, the “commonsense” that precedes logic. If reality is not commonsense, what is? And doubting the realness of reality, almost by definition, is stepping outside the bounds of mythos. So it fits; my concerns were indeed well-founded.

But a good fit is no guarantee of the “rightness” of a hypothesis, as Zen and the Art of Motorcycle Maintenance teaches us. Given enough time, we can always come up with a hypothesis that fits our observations. The process of hypothesizing from observations and experiences is like trying to guess the nature of an object from the shadow it projects. And a projection is precisely what our reality is — a projection of unknown forms and processes into our sensory and cognitive space, into our mythos and logos. But here, I may be pushing my own agenda rather than the theme of the book. But it does fit, doesn’t it? That is why I found myself muttering “Exactly!” over and over during my three reads of the book, and why I will read it many more times in the future. Let’s remind ourselves again, a good fit says nothing about the rightness of a hypothesis.

One such reasonable hypothesis of ours is about continuity We all assume the continuity of our personality or selfhood, which is a bit strange. I know that I am the same person I was twenty years ago — older certainly, wiser perhaps, but still the same person. But from science, I also know for a fact that every cell, every atom and every little fundamental particle in my body now is different from what constituted my body then. The potassium in the banana I ate two weeks ago is, for instance, what may be controlling the neuronal firing behind the thought process helping me write this essay. But it is still me, not the banana. We all assume this continuity because it fits.

Losing this continuity of personality is a scary thought. How scary it is is what Zen and the Art of Motorcycle Maintenance tells you. As usual, I’m getting a bit ahead of myself. Let’s start at the beginning.

In order to write a decent review of this book, it is necessary to summarize the “story” (which is believed to be based on the author’s life). Like most great works of literature, the story flows inwards and outwards. Outwardly, it is a story of a father and son (Pirsig and Chris) across the vast open spaces of America on a motorbike. Inwardly, it is a spiritual journey of self-discovery and surprising realizations. At an even deeper level, it is a journey towards possible enlightenment rediscovered.

The story begins with Pirsig and Chris riding with John and Sylvia. Right at the first unpretentious sentence, “I can see by my watch, without taking my hand from the left grip of the cycle, that it is eight-thirty in the morning,” it hit me that this was no ordinary book — the story is happening in the present tense. It is here and now — the underlying Zen-ness flows from the first short opening line and never stops.

The story slowly develops into the alienation between Chris and his father. The “father” comes across as a “selfish bastard,” as one of my friends observed.

The explanation for this disconnect between the father and the son soon follows. The narrator is not the father. He has the father’s body all right, but the real father had his personality erased through involuntary shock treatments. The doctor had reassured him that he had a new personality — not that he was a new personality.

The subtle difference makes ample sense once we realize that “he” and his “personality” are not two. And, to those of us how believe in the continuity of things like self-hood, it is a very scary statement. Personality is not something you have and wear, like a suit or a dress; it is what you are. If it can change, and you can get a new one, what does it say about what you think you are?

In Pirsig’s case, the annihilation of the old personality was not perfect. Besides, Chris was tagging along waiting for that personality to wake up. But awakening a personality is very different from waking a person up. It means waking up all the associated thoughts and ideas, insights and enlightenment. And wake up it does in this story — Phaedrus is back by the time we reach the last pages of the book.

What makes this book such a resounding success, (not merely in the market, but as an intellectual endeavor) are the notions and insights from Phaedrus that Pirsig manages to elicit. Zen and the Art of Motorcycle Maintenance is nothing short of a new way of looking at reality. It is a battle for the minds, yours and mine, and those yet to come.

Such a battle was waged and won ages ago, and the victors were not gracious and noble enough to let the defeated worldview survive. They used a deadly dialectical knife and sliced up our worldview into an unwieldy duality. The right schism, according to Phaedrus and/or Pirsig, would have been a trinity.

The trinity managed to survive, albeit feebly, as a vanquished hero, timid and self-effacing. We see it in the Bible, for instance, as the Father, the Son and the Holy Spirit. We see it Hinduism, as its three main gods, and in Vedanta, a line of thought I am more at home with, as Satyam, Shivam, Sundaram — the Truth, ???, the Beauty. The reason why I don’t know what exactly Shivam means indicates how the battle for the future minds was won by the dualists.

It matters little that the experts in Vedanta and the Indian philosophical schools may know precisely what Shivam signifies. I for one, and the countless millions like me, will never know it with the clarity with which we know the other two terms — Sundaram and Satyam, beauty and truth, Maya and Brahman, aesthetics and metaphysics, mind and matter. The dualists have so completely annihilated the third entity that it does not even make sense now to ask what it is. They have won.

Phaedrus did ask the question, and found the answer to be Quality — something that sits in between mind and matter, between a romantic and a classical understanding of the world. Something that we have to and do experience before our intellect has a chance to process and analyze it. Zen.

However, in doing so, Phaedrus steps outside our mythos, and is hence insane.

If insanity is Zen, then my old friend was right. Sanity is way overrated.

Photo by MonsieurLui

Articles and Essays, Philosophy, Physics

Perception, Physics and the Role of Light in Philosophy

Reality, as we sense it, is not quite real. The stars we see in the night sky, for instance, are not really there. They may have moved or even died by the time we get to see them. This unreality is due to the time it takes for light from the distant stars and galaxies to reach us. We know of this delay.

Even the sun that we know so well is already eight minutes old by the time we see it. This fact does not seem to present particularly grave epistemological problems – if we want to know what is going on at the sun now, all we have to do is to wait for eight minutes. We only have to ‘correct’ for the distortions in our perception due to the finite speed of light before we can trust what we see. The same phenomenon in seeing has a lesser-known manifestation in the way we perceive moving objects. Some heavenly bodies appear as though they are moving several times the speed of light, whereas their ‘real’ speed must be a lot less than that.

What is surprising (and seldom highlighted) is that when it comes to sensing motion, we cannot back-calculate in the same kind of way as we can to correct for the delay in observation of the sun. If we see a celestial body moving at an improbably high speed, we cannot calculate how fast or even in what direction it is ‘really’ moving without first having to make certain further assumptions.

Einstein chose to resolve the problem by treating perception as distorted and inventing new fundamental properties in the arena of physics – in the description of space and time. One core idea of the Special Theory of Relativity is that the human notion of an orderly sequence of events in time needs to be abandoned. In fact, since it takes time for light from an event at a distant place to reach us, and for us to become aware of it, the concept of ‘now’ no longer makes any sense, for example, when we speak of a sunspot appearing on the surface of the sun just at the moment that the astronomer was trying to photograph it. Simultaneity is relative.

Einstein instead redefined simultaneity by using the instants in time we detect the event. Detection, as he defined it, involves a round-trip travel of light similar to radar detection. We send out a signal travelling at the speed of light, and wait for the reflection. If the reflected pulse from two events reaches us at the same instant, then they are simultaneous. But another way of looking at it is simply to call two events ‘simultaneous’ if the light from them reaches us at the same instant. In other words, we can use the light generated by the objects under observation rather than sending signals to them and looking at the reflection.

This difference may sound like a hair-splitting technicality, but it does make an enormous difference to the predictions we can make. Einstein’s choice results in a mathematical picture that has many desirable properties, including that of making further theoretical development more elegant. But then, Einstein believed, as a matter of faith it would seem, that the rules governing the universe must be ‘elegant.’ However, the other approach has an advantage when it comes to describing objects in motion. Because, of course, we don’t use radar to see the stars in motion; we merely sense the light (or other radiation) coming from them. Yet using this kind of sensory paradigm, rather than ‘radar-like detection,’ to describe the universe results in an uglier mathematical picture. Einstein would not approve!

The mathematical difference spawns different philosophical stances, which in turn percolate to the understanding of our physical picture of reality. As an illustration, suppose we observe, through a radio telescope, two objects in the sky, with roughly the same shape, size and properties. The only thing we know for sure is that the radio waves from these two different points in the sky reach us at the same instant in time. We can only guess when the waves started their journeys.

If we assume (as we routinely do) that the waves started the journey roughly at the same instant in time, we end up with a picture of two ‘real’ symmetric lobes more or less the way see them. But there is another, different possibility and that is that the waves originated from the same object (which is in motion) at two different instants in time, reaching the telescope at the same instant. This possibility would additionally explain some spectral and temporal properties of such symmetric radio sources. So which of these two pictures should we take as real? Two symmetric objects as we see them or one object moving in such a way as to give us that impression? Does it really matter which one is ‘real’? Does ‘real’ mean anything in this context?

Special Relativity gives an unambiguous answer to this question. The mathematics rules out the possibility of a single object moving in such a fashion as to mimic two objects. Essentially, what we see is what is out there. Yet, if we define events by what we perceive, the only philosophical stance that makes sense is the one that disconnects the sensed reality from the causes lying behind what is being sensed.

This disconnect is not uncommon in philosophical schools of thought. Phenomenalism, for instance, holds the view that space and time are not objective realities. They are merely the medium of our perception. All the phenomena that happen in space and time are merely bundles of our perception. In other words, space and time are cognitive constructs arising from perception. Thus, all the physical properties that we ascribe to space and time can only apply to the phenomenal reality (the reality of ‘things-in-the-world’ as we sense it. The underlying reality (which holds the physical causes of our perception), by contrast, remains beyond our cognitive reach.

Yet there is a chasm between the views of philosophy and modern physics. Not for nothing did the Nobel Prize winning physicist, Steven Weinberg, wonder, in his book Dreams of a Final Theory, why the contribution from philosophy to physics had been so surprisingly small. Perhaps it is because physics has yet to come to terms with the fact that when it comes to seeing the universe, there is no such thing as an optical illusion – which is probably what Goethe meant when he said, ‘Optical illusion is optical truth.’

The distinction (or lack thereof) between optical illusion and truth is one of the oldest debates in philosophy. After all, it is about the distinction between knowledge and reality. Knowledge is considered our view about something that, in reality, is ‘actually the case.’ In other words, knowledge is a reflection, or a mental image of something external, as shown in the figure below.

ExternalToBrain

In this picture, the black arrow represents the process of creating knowledge, which includes perception, cognitive activities, and the exercise of pure reason. This is the picture that physics has come to accept. While acknowledging that our perception may be imperfect, physics assumes that we can get closer and closer to the external reality through increasingly finer experimentation, and, more importantly, through better theorization. The Special and General Theories of Relativity are examples of brilliant applications of this view of reality where simple physical principles are relentlessly pursued using formidable machine of pure reason to their logically inevitable conclusions.

But there is another, alternative view of knowledge and reality that has been around for a long time. This is the view that regards perceived reality as an internal cognitive representation of our sensory inputs, as illustrated below.

AbsolutelToBrain

In this view, knowledge and perceived reality are both internal cognitive constructs, although we have come to think of them as separate. What is external is not the reality as we perceive it, but an unknowable entity giving rise to the physical causes behind sensory inputs. In the illustration, the first arrow represents the process of sensing, and the second arrow represents the cognitive and logical reasoning steps. In order to apply this view of reality and knowledge, we have to guess the nature of the absolute reality, unknowable as it is. One possible candidate for the absolute reality is Newtonian mechanics, which gives a reasonable prediction for our perceived reality.

To summarize, when we try to handle the distortions due to perception, we have two options, or two possible philosophical stances. One is to accept the distortions as part of our space and time, as Special Relativity does. The other option is to assume that there is a ‘higher’ reality distinct from our sensed reality, whose properties we can only conjecture. In other words, one option is to live with the distortion, while the other is to propose educated guesses for the higher reality. Neither of these choices is particularly attractive. But the guessing path is similar to the view accepted in phenomenalism. It also leads naturally to how reality is viewed in cognitive neuroscience, which studies the biological mechanisms behind cognition.

The twist to this story of light and reality is that we seem to have known all this for a long time. The role of light in creating our reality or universe is at the heart of Western religious thinking. A universe devoid of light is not simply a world where you have switched off the lights. It is indeed a universe devoid of itself, a universe that doesn’t exist. It is in this context that we have to understand the wisdom behind the statement that ‘the earth was without form, and void’ until God caused light to be, by saying ‘Let there be light.’

The Koran also says, ‘Allah is the light of the heavens and the earth,’ which is mirrored in one of the ancient Hindu writings: ‘Lead me from darkness to light, lead me from the unreal to the real.’ The role of light in taking us from the unreal void (the nothingness) to a reality was indeed understood for a long, long time. Is it possible that the ancient saints and prophets knew things that we are only now beginning to uncover with all our supposed advances in knowledge?

There are parallels between the noumenal-phenomenal distinction of Kant and the phenomenalists later, and the Brahman-Maya distinction in Advaita. Wisdom on the nature of reality from the repertoire of spirituality is reinvented in modern neuroscience, which treats reality as a cognitive representation created by the brain. The brain uses the sensory inputs, memory, consciousness, and even language as ingredients in concocting our sense of reality. This view of reality, however, is something physics is still unable to come to terms with. But to the extent that its arena (space and time) is a part of reality, physics is not immune to philosophy.

In fact, as we push the boundaries of our knowledge further and further, we are discovering hitherto unsuspected and often surprising interconnections between different branches of human efforts. Yet, how can the diverse domains of our knowledge be independent of each other if all knowledge is subjective? If knowledge is merely the cognitive representation of our experiences? But then, it is the modern fallacy to think that knowledge is our internal representation of an external reality, and therefore distinct from it. Instead, recognising and making use of the interconnections among the different domains of human endeavour may be the essential prerequisite for the next stage in developing our collective wisdom.

Box: Einstein’s TrainOne of Einstein’s famous thought experiments illustrates the need to rethink what we mean by simultaneous events. It describes a high-speed train rushing along a straight track past a small station as a man stands on the station platform watching it speed by. To his amazement, as the train passes him, two lightening bolts strike the track next to either end of the train! (Conveniently, for later investigators, they leave burn marks both on the train and on the ground.)

To the man, it seems that the two lightening bolts strike at exactly the same moment. Later, the marks on the ground by the train track reveal that the spots where the lightening struck were exactly equidistant from him. Since then the lightening bolts travelled the same distance towards him, and since they appeared to the man to happen at exactly the same moment, he has no reason not to conclude that the lightening bolts struck at exactly the same moment. They were simultaneous.

However, suppose a little later, the man meets a lady passenger who happened to be sitting in the buffet car, exactly at the centre of the train, and looking out of the window at the time the lightening bolts struck. This passenger tells him that she saw the first lightening bolt hit the ground near the engine at the front of the train slightly ahead of when the second one hit the ground next to the luggage car at the rear of the train.

The effect has nothing to do with the distance the light had to travel, as both the woman and the man were equidistant between the two points that the lightening hit. Yet they observed the sequence of events quite differently.

This disagreement of the timing of the events is inevitable, Einstein says, as the woman is in effect moving towards the point where the flash of lightening hit near the engine -and away from the point where the flash of lightening hit next to the luggage car. In the tiny amount of time it takes for the light rays to reach the lady, because the train moves, the distance the first flash must travel to her shrinks, and the distance the second flash must travel grows.

This fact may not be noticed in the case of trains and aeroplanes, but when it comes to cosmological distances, simultaneity really doesn’t make any sense. For instance, the explosion of two distant supernovae, seen as simultaneous from our vantage point on the earth, will appear to occur in different time combinations from other perspectives.

In Relativity: The Special and General Theory (1920), Einstein put it this way:

‘Every reference-body (co-ordinate system) has its own particular time; unless we are told the reference-body to which the statement of time refers, there is no meaning in a statement of the time of an event.’

Creative, Work and Life

The Story So Far …

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In the early sixties, Santa Kumari Amma decided to move to the High Ranges. She had recently started working with KSEB which was building a hydro-electric project there.The place was generically called the High Ranges, even though the ranges weren’t all that high. People told her that the rough and tough High Ranges were no place for a country girl like her, but she wanted to go anyways, prompted mainly by the fact that there was some project allowance involved and she could use any little bit that came her way. Her family was quite poor. She came from a small village called Murani (near a larger village called Mallappalli.)

Around the same time B. Thulasidas (better known as Appu) also came to the High Ranges. His familty wasn’t all that poor and he didn’t really need the extra money. But he thought, hey rowdy place anyway, what the heck? Well, to make a long story short, they fell in love and decided to get married. This was some time in September 1962. A year later Sandya was born in Nov 63. And a little over another year and I came to be! (This whole stroy, by the way, is taking place in the state of Kerala in India. Well, that sentence was added just to put the links there, just in case you are interested.) There is a gorgeous hill resort called Munnar (meaning three rivers) where my parents were employed at that time and that’s where I was born.

[casual picture] Just before 1970, they (and me, which makes it we I guess) moved to Trivandrum, the capital city of Kerala. I lived in Trivandrum till I was 17. Lots of things happened in those years, but since this post is still (and always will be) work in progress, I can’t tell you all about it now.

In 1983, I moved to Madras, to do my BTech in Electronics and Communication at IIT, Madras. (They call the IITs the MIT of India, only much harder to get in. In my batch, there were about 75,000 students competing for about 2000 places. I was ranked 63 among them. I’m quite smart academically, you see.) And as you can imagine, lots of things happened in those four years as well. But despite all that, I graduated in August 1987 and got my BTech degree.

In 1987, after finishing my BTech, I did what most IITians are supposed to do. I moved to the states. Upstate New York was my destination. I joined the Physics Department of Syracuse University to do my PhD in High Energy Physics. And boy, did a lot of things happen during those 6 years! Half of those 6 years were spent at Cornell University in Ithaca.

That was in Aug. 1987. Then in 1993 Sept, the prestigious French national research organization ( CNRS – “Centre national de la recherche scientifique”) hired me. I moved to France to continue my research work at ALEPH, CERN. My destination in France was the provencal city of Marseilles. My home institute was “Centre de Physique des Particules de Marseille” or CPPM. Of course, I didn’t speak a word of French, but that didn’t bother me much. (Before going to the US in 1987, I didn’t speak much English/Americanese either.)

End of 1995, on the 29th of Dec, I got married to Kavita. In early 1996, Kavita also moved to France. Kavita wasn’t too happy in France because she felt she could do much more in Singapore. She was right. Kavita is now an accomplished entrepreneur with two boutiques in Singapore and more business ideas than is good for her. She has won many awards and is a minor celebrity with the Singapore media. [Wedding picture]

In 1998, I got a good offer from what is now the Institute for Infocomm Research and we decided to move to Singapore. Among the various personal reasons for the move, I should mention that the smell of racisim in the Marseilles air was one. Although every individual I personally met in France was great, I always had a nagging feeling that every one I did not meet wanted me out of there. This feeling was further confirmed by the immigration clerks at the Marignane airport constantly asking me to “Mettez-vous a cote, monsieur” and occassionally murmuring “les francais d’abord.” [Anita Smiles]

A week after I moved to Singapore, on the 24rth of July 1998, Anita was born. Incredibly cute and happy, Anita rearranged our priorities and put things in perspective. Five years later, on the 2nd of May 2003, Neil was born. He proved to be even more full of smiles. [Neil Smiles more!]

In Singapore, I worked on a lot of various body-based measurements generating several patents and papers. Towards the end of my career with A-Star, I worked on brain signals, worrying about how to make sense of them and make them talk directly to a computer. This research direction influenced my thinking tremendously, though not in a way my employer would’ve liked. I started thinking about the role of perception in our world view and, consequently, in the theories of physics. I also realized how these ideas were not isolated musings, but were atriculated in various schools of philosophy. This line of thinking eventually ended up in my book, The Unreal Universe.

Towards the second half of 2005, I decided to chuck research and get into quantitative finance, which is an ideal domain for a cash-strapped physicist. It turned out that I had some skills and aptitudes that were mutually lucrative to my employers and myself. My first job was as the head of the quantitative analyst team at OCBC, a regional bank in Singapore. This middle office job, involving risk management and curtailing ebullient traders, gave me a thorough overview of pricing models and, perhaps more importantly, perfect understanding of the conflict-driven implementation of the risk appetite of the bank.

[Dad] Later on, in 2007, I moved to Standard Chartered Bank, as a senior quantitative professional taking care of their in-house trading platform, which further enhanced my "big picture" outlook and inspired me to write Principles of Quantitative Development. I am rather well recognized in my field, and as a regular columnist for the Wilmott Magazine, I have published several articles on a variety of topics related to quants and quantitative finance, which is probably why John Wiley & Sons Ltd. asked me to write this book.

Despite these professional successes, on the personal front, 2008 has been a year of sadness. I lost my father on the 22nd of October. The death of a parent is a rude wake-up call. It brings about feelings of loss and pain that are hard to understand, and impossible to communicate. And for those of us with little gift of easy self-expression, they linger for longer than they perhaps should.