Tag Archives: physical reality

Sensory and Physical Worlds

Animals have different sensory capabilities compared to us humans. Cats, for instance, can hear up to 60kHz, while the highest note we have ever heard was about 20kHz. Apparently, we could hear that high a note only in our childhood. So, if we are trying to pull a fast one on a cat with the best hifi multi-channel, Dolby-whatever recording of a mouse, we will fail pathetically. It won’t be fooled because it lives in a different sensory world, while sharing the same physical world as ours. There is a humongous difference between the sensory and physical worlds.

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What is Unreal Blog?

Tell us a little about why you started your blog, and what keeps you motivated about it.

As my writings started appearing in different magazines and newspapers as regular columns, I wanted to collect them in one placeas an anthology of the internet kind, as it were. That’s how my blog was born. The motivation to continue blogging comes from the memory of how my first book, The Unreal Universe, took shape out of the random notes I started writing on scrap books. I believe the ideas that cross anybody’s mind often get forgotten and lost unless they are written down. A blog is a convenient platform to put them down. And, since the blog is rather public, you take some care and effort to express yourself well.

Do you have any plans for the blog in the future?

I will keep blogging, roughly at the rate of one post a week or so. I don’t have any big plans for the blog per se, but I do have some other Internet ideas that may spring from my blog.

Philosophy is usually seen as a very high concept, intellectual subject. Do you think that it can have a greater impact in the world at large?

This is a question that troubled me for a while. And I wrote a post on it, which may answer it to the best of my ability. To repeat myself a bit, philosophy is merely a description of whatever intellectual pursuits that we indulge in. It is just that we don’t often see it that way. For instance, if you are doing physics, you think that you are quite far removed from philosophy. The philosophical spins that you put on a theory in physics is mostly an afterthought, it is believed. But there are instances where you can actually apply philosophy to solve problems in physics, and come up with new theories. This indeed is the theme of my book, The Unreal Universe. It asks the question, if some object flew by faster than the speed of light, what would it look like? With the recent discovery that solid matter does travel faster than light, I feel vindicated and look forward to further developments in physics.

Do you think many college students are attracted to philosophy? What would make them choose to major in it?

In today’s world, I am afraid philosophy is supremely irrelevant. So it may be difficult to get our youngsters interested in philosophy. I feel that one can hope to improve its relevance by pointing out the interconnections between whatever it is that we do and the intellectual aspects behind it. Would that make them choose to major in it? In a world driven by excesses, it may not be enough. Then again, it is world where articulation is often mistaken for accomplishments. Perhaps philosophy can help you articulate better, sound really cool and impress that girl you have been afterto put it crudely.

More seriously, though, what I said about the irrelevance of philosophy can be said about, say, physics as well, despite the fact that it gives you computers and iPads. For instance, when Copernicus came up with the notion that the earth is revolving around the sun rather than the other way round, profound though this revelation was, in what way did it change our daily life? Do you really have to know this piece of information to live your life? This irrelevance of such profound facts and theories bothered scientists like Richard Feynman.

What kind of advice or recommendations would you give to someone who is interested in philosophy, and who would like to start learning more about it?

I started my path toward philosophy via physics. I think philosophy by itself is too detached from anything else that you cannot really start with it. You have to find your way toward it from whatever your work entails, and then expand from there. At least, that’s how I did it, and that way made it very real. When you ask yourself a question like what is space (so that you can understand what it means to say that space contracts, for instance), the answers you get are very relevant. They are not some philosophical gibberish. I think similar paths to relevance exist in all fields. See for example how Pirsig brought out the notion of quality in his work, not as an abstract definition, but as an all-consuming (and eventually dangerous) obsession.

In my view, philosophy is a wrapper around multiple silos of human endeavor. It helps you see the links among seemingly unrelated fields, such as cognitive neuroscience and special relativity. Of what practical use is this knowledge, I cannot tell you. Then again, of what practical use is life itself?

Why the Speed of Light?

What is so special about light that its speed should figure in the basic structure of space and time and our reality? This is the question that has nagged many scientists ever since Albert Einstein published On the Electrodynamics of Moving Bodies about 100 years ago.

In order to understand the specialness of light in our space and time, we need to study how we perceive the world around us and how reality is created in our brains. We perceive our world using our senses. The sensory signals that our senses collect are then relayed to our brains. The brain creates a cognitive model, a representation of the sensory inputs, and presents it to our conscious awareness as reality. Our visual reality consists of space much like our auditory world is made up of sounds.

Just as sounds are a perceptual experience rather than a fundamental property of the physical reality, space also is an experience, or a cognitive representation of the visual inputs, not a fundamental aspect ofthe worldour senses are trying to sense.

Space and time together form what physics considers the basis of reality. The only way we can understand the limitations in our reality is by studying the limitations in our senses themselves.

At a fundamental level, how do our senses work? Our sense of sight operates using light, and the fundamental interaction involved in sight falls in the electromagnetic (EM) category because light (or photon) is the intermediary of EM interactions. The exclusivity of EM interaction is not limited to our the long range sense of sight; all the short range senses (touch, taste, smell and hearing) are also EM in nature. To understand the limitations of our perception of space, we need not highlight the EM nature of all our senses. Space is, 总的来说,,en,我们常识的数学演绎,,en,处理人类规模的现象,,en,一旦我们突破了知觉装置的界限,,en,然而,,en,我们无权根据我们的常识期望事物遵循框架,,en,只是不适用于这些域,,en,粒子及其相互作用存在于我们常识之外的现实中,,en,如果你考虑一下,,en,一定是那样,,en,水分子的组成,,en,即氢和氧,,en,别像水一样,,en,原子的组成,,en,电子和质子,,en,不必表现任何类似的事情,,en,粒子不是物质的小液滴,,en,它们是奇怪的实体,其属性我们无法直观地把握,,en, the result of our sight sense. But it is worthwhile to keep in mind that we would have no sensing, and indeed no reality, in the absence of EM interactions.

Like our senses, all our technological extensions to our senses (such as radio telescopes, electron microscopes, redshift measurements and even gravitational lensing) use EM interactions exclusively to measure our universe. Thus, we cannot escape the basic constraints of our perception even when we use modern instruments. 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 perceived reality, whether built upon direct sensory inputs or technologically enhanced, is a subset of electromagnetic particles and interactions only. It is a projection of EM particles and interactions into our sensory and cognitive space, a possibly imperfect projection.

This statement about the exclusivity of EM interactions in our perceived reality is often met with a bit of skepticism, mainly due to a misconception that we can sense gravity directly. This confusion arises because our bodies are subject to gravity. There is a fine distinction betweenbeing subject to” and “being able to sensegravitational force.

This difference is illustrated by a simple thought experiment: Imagine a human subject placed in front of an object made entirely of cosmological dark matter. There is no other visible matter anywhere the subject can see it. Given that the dark matter exerts gravitational force on the subject, will he be able to sense its presence? He will be pulled toward it, but how will he know that he is being pulled or that he is moving? He can possibly design some mechanical contraption to detect the gravity of the dark matter object. But then he will be sensing the effect of gravity on some matter using EM interactions. For instance, he may be able to see his unexplained acceleration (effect of gravity on his body, which is EM matter) with respect to reference objects such as stars. But the sensing part here (seeing the stars) involves EM interactions.

It is impossible to design any mechanical contraption to detect gravity that is devoid of EM matter. The gravity sensing in our ears again measures the effect of gravity on EM matter. In the absence of EM interaction, it is impossible to sense gravity, or anything else for that matter.

Electromagnetic interactions are responsible for our sensory inputs. Sensory perception leads to our brain’s representation that we call reality. Any limitation in this chain leads to a corresponding limitation in our sense of reality. One limitation in the chain from senses to reality is the finite speed of photon, which is the gauge boson of our senses. The finite speed of the sense modality influences and distorts our perception of motion, space and time. Because these distortions are perceived as a part of our reality itself, the root cause of the distortion becomes a fundamental property of our reality. This is how the speed of light becomes such an important constant in our space time. The sanctity of light is respected only in our perceived reality.

If we trust the imperfect perception and try to describe what we sense at cosmological scales, we end up with views of the world such as the big bang theory in modern cosmology and the general and special theories of relativity. These theories are not wrong, and the purpose of this book is not to prove them wrong, just to point out that they are descriptions of a perceived reality. They do not describe the physical causes behind the sensory inputs. The physical causes belong to an absolute reality beyond our senses.

The distinction between the absolute reality and our perception of it can be further developed and applied to certain specific astrophysical and cosmological phenomena. When it comes to the physics that happens well beyond our sensory ranges, we really have to take into account the role that our perception and cognition play in seeing them. The universe as we see it is only a cognitive model created out of the photons falling on our retina or on the photo sensors of the Hubble telescope. Because of the finite speed of the information carrier (namely photons), our perception is distorted in such a way as to give us the impression that space and time obey special relativity. They do, but space and time are not the absolute reality. They are only a part of the unreal universe that is our perception of an unknowable reality.

[This again is an edited excerpt from my book, The Unreal Universe.]