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Author Topic: At the speed of light, does time stop?  (Read 17581 times)

Offline JP

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Re: At the speed of light, does time stop?
« Reply #50 on: 11/03/2013 14:08:19 »
Would you like to expand on how they are the same, and from which point of view JP? You talk about a classical wave here, meaning a wave close to waves we see in nature I presume. But from where would one find them to be the same, a field?

A classical wave looks like a sinusoid and has wavelength that's a distance over space and period that's an oscillation in time.  This comes about from classical models of the EM field, i.e. what are known as Maxwell's equations. 

The photon is a more fundamental model of the field as a particle with a fixed energy.  Since a photon is a more fundamental building block, it's possible to build up a classical wave by adding a bunch of photons together in the right way. 

The connection comes when you measure many photons and their average properties start to look like a classical wave.  If you measure a single photon out of a classical wave, it might hit your detector at a point, which would seem to be less than the wavelength of a classical wave.  But if you ask where the next photon will hit, you can only predict that to, at best, roughly one wavelength.  If you measure many phtons, you'll find that they, at best, collect in a spot of about a wavelength in size.
 

Offline yor_on

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Re: At the speed of light, does time stop?
« Reply #51 on: 11/03/2013 22:45:39 »
So when you measure a lot of photons hitting a detector, would you mean that they are spaced out in the form of wave? And, at about one wavelength apart, would that be a ratio found statistically, or measuring where they hit? It also has to do with the logic of the mathematics, right? I need to know more :) And thnx.
 

Offline lightarrow

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Re: At the speed of light, does time stop?
« Reply #52 on: 11/03/2013 22:58:56 »
Better point out Lean Bean that we both become 'realists' here, especially if you agree. We expect things to make a real sense, in a experiment. We expect clear definitions of what light can, and can not do.
In the 1984~1985 I began to ask people (professors and students) at university: "what *really* is a photon"? I believed it should be something simple, or at least something that should have a clear definition of it as "physical object"; but I discovered that people were actually continuously talking about ... ghosts  :)
From a certain point of view the definition is quite simple, the first one I received (from an older student than me): "the quantum of the electromagnetic field". But I was looking for something more ... actual, like: "it's a little ball", or "it's the simple clicking of the detector", etc.

Many years passed and even if I read a lot about the subject, the "image" of what a photon is, hasn't become more clear, it has become even more "ghostly"!

Please, if you succeed in finding a simple picture of what a photon really is, write me immediately!

For the moment, you can read:
http://www.sheffield.ac.uk/polopoly_fs/1.14183!/file/photon.pdf
« Last Edit: 11/03/2013 23:09:55 by lightarrow »
 

Offline yor_on

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Re: At the speed of light, does time stop?
« Reply #53 on: 11/03/2013 23:55:02 »
Thnx lightarrow, and I will read it :)

And yeah, for me photons seemed simpler than waves in some ways. And as I'm terribly lazy I prefer simple :) But the more I looked at people explaining, the more weird they seemed to become. Then I started to look at waves, as you well know, and my headache didn't get any better. Nowadays I suspect that the only thing I'm really sure of is that we do communicate :)
==

Very nice paper Lightarrow.
« Last Edit: 12/03/2013 00:31:17 by yor_on »
 

Offline yor_on

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Re: At the speed of light, does time stop?
« Reply #54 on: 12/03/2013 01:12:03 »
The one making me most confounded is the one referring to a photon as a 'quantum rotator'. Never heard that one before? What the he* would that mean? Looking it up on the net the only papers I see seem to discuss some 'quantum aether'? I knew i should have stayed away from this one :)
=
Heh

'I don't know anything about photons, but I sure know one when I see it' is the one I get :)

==
Found it

" I work on reconciling the fundamental concepts and principles of quantum theory and space-time theory, Einstein and Heisenberg, by quantizing the infrastructure of present quantum field theory, a process of "infra-quantization". I model the field system as a quantum simplicial complex in the form of a truss dome composed of spins. This quantizes both space-time and the imaginary I of quantum theory. It invokes an organizational symmetry-rearrangement to recover the canonical quantum theory, which assumes that they are classical.

Quantum simplices are represented in a typed exterior algebra. Physical theories today are based on Lie algebras. Taken modulo isomorphism these form a (moduli) space of rich structure, a rugged landscape. Its peaks and ridges are singular groups without useful finite representations. They are flanked by regular Lie algebras with useful finite-dimensional representations, including simple Lie algebras. Early theorists built their castles on the peaks, mainly for ideological reasons. As a result these theories proved to be infested with infinities. Heisenberg's quantization moved theories from peaks to adjacent ridges, rendering them less singular. Infraquantization moves them to the valley, specifically to finite-dimensional matrix algebras. The main question now under study is how to compute the excitation spectrum of a quantum truss dome and align it with the particle spectrum. This would also fix the quantum of time

Questions under study:

Q1. How big is a chronon? The Planck-length estimate for tav is too non-operational to be trusted?

Q2. How do space-time and field theory emerge as a self-organization of a simple quantum dynamics in the limit as the chronon size goes to zero?

Q3. How do we account for the details of the particles of nature as quantum excitations in the dynamic relative to its vacuum value?

Q4. What are the experimental high-energy-physics consequences of the general-quantization already carried out?"

Nothing to do with those papers I first saw. And his presentation was really nice.
« Last Edit: 12/03/2013 01:34:59 by yor_on »
 

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Re: At the speed of light, does time stop?
« Reply #54 on: 12/03/2013 01:12:03 »

 

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