**Thu,** 五月 24, 2007 在 5:25 AM Hi Ranga,

I will reply in detail later, but want to respond to a couple of points. One is about how to prove that there is no light barrier in AR. As you rightly pointed out, I can’t. In my view, I don’t think one needs to prove it. Let me put it this way — suppose we lived in box. One fine morning, we find an arc from one wall to another. Then one bright handsome guy (me 🙂 comes up with the notion that the arc is a part of a big circle outside the box. There is no way to prove it because we cannot see outside the box. 除了, it may simply be wrong. But the notion is consistent with the arc. If there are other measurements (such as the observed travel time of an object disappearing at one wall and reappearing at the other end being consistent with the perimeter of the circle), we can have some confidence on the notion. This is roughly where I am. I have an explanation why the speed of light appears in our perception of motion, and I have some other observations (GRBs, radio jets etc) that are consistent with the explanation.

Now about whose PR I am talking about, it is the PR that is created by light. Specifically, the perception of motion as measured using light. About the presence of other senses that don’t seem to rely on light — all the interactions that we are capable of sensing are of electromagnetic variety. And photon is the mediating boson for EM interactions in QED. So it can be argued that we sense only EM matter using photon. I have quite a bit more about it in my book.

About the blind man’s sense of space, the answer lies in the role of language in creating our reality. Language serves to normalize our separate perceptual realities. In order to appreciate its role fully, we have to find someone who didn’t have a language for sometime and then acquired it. Like Helen Keller. I went into it in some detail in the book. My point is, if you had a bunch of isolated blind people (as a blind civilization with its own language), I don’t think they will have a cognitive representation of space. 同样, another assertion that cannot be tested or verified.

Coming back to the need to validate my “model” for AR — we have a pretty good idea of how our senses work at a macro level. 我的意思是, when we look at a star a million light years away, we know that what we are seeing is what happened a million years ago. This time delay is a first order effect of the finite speed of light. A second order effect is the manifestation of the finite speed of light in our perception of motion. We cannot deconvolute out this manifestation from our perception of motion (one reason why the PR->AR mapping is one to many). 然而, given a model, we can certainly verify whether it is consistent with our PR.

Just like verifiability, falsifiability is also a required feature of a theory. I do list a couple of features of GRBs and radio jets that, if observed, would prove that my theory is wrong.

The reason for light to be special in my explanation is not my physicist’s preference in terms of mass-energy equation (the validity of which, I’m slightly skeptical of right now :). It is just because space is the representation of our sight sense. Much like sound is a product of hearing — an analogy I go into in some length in the book.

When we see things moving in our space representation, our brain’s assumption is that the speed of light is infinite. The deconvolution I was talking about (modeling AR from PR) is an effort to imagine a space where the speed of light is really infinity. You then apply the finite speed and work out how our perception will be distorted due to this finite speed. SR (the coordinate transformation part) is really a mapping of the speed of light to infinity. 同样, a notion I illustrate in the book.

I feel as though I’m rewriting my book in my emails to you, without the benefit of being able to present the ideas in a structured and convincing manner. You are going to have to read the book!

I don’t remember whether we have talked about observed superluminality? Another point I have to get into when I have some more time.

– cheers,

– 手

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