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Author Topic: Photons and Special Theory of Relativity ?  (Read 6773 times)

Offline Bill S

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Re: Photons and Special Theory of Relativity ?
« Reply #25 on: 29/12/2011 16:39:42 »
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I thought Yor_on and JP were serious.

You lost me there, Simplified, just when I thought I'd kept a handle on the thread. :(
 

Offline Bill S

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Re: Photons and Special Theory of Relativity ?
« Reply #26 on: 29/12/2011 18:09:08 »
Quote from: JP
Time doesn't actually stand still for a photon according to our theories.

Could we have some more information about these theories, please.
 

Offline imatfaal

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Re: Photons and Special Theory of Relativity ?
« Reply #27 on: 30/12/2011 10:29:55 »
Quote from: JP
Time doesn't actually stand still for a photon according to our theories.

Could we have some more information about these theories, please.

The time standing still is an extrapolation of SR - but it is not really a correct one. 

SR uses the formula 3bef102aa38c5ccd915d0b70bd69d26a.gif

For a massive object as it approaches c the bottom of the fraction will approach zero - and time dilation will become more and more pronounced when viewed from a local FoR in relative rest.  It might seem for an outside observer that time has completely stopped as an object reaches c - but SR is quite clear on the fact that a frame of reference of the photon or any other massless particle which must be travelling at c is not defined (you need to be able to define an inertial frame where the photon is at rest and that is a nono), you cannot just extrapolate that equation.
 

Offline simplified

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Re: Photons and Special Theory of Relativity ?
« Reply #28 on: 30/12/2011 15:08:10 »
Quote
I thought Yor_on and JP were serious.

You lost me there, Simplified, just when I thought I'd kept a handle on the thread. :(
You were lost earlier. They tried to prove probable inability of the moon to block a way of a visible photon(length of wave has meaning) even by central part . :P
« Last Edit: 30/12/2011 15:20:13 by simplified »
 

Offline JP

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Re: Photons and Special Theory of Relativity ?
« Reply #29 on: 30/12/2011 15:50:16 »
I suggest you reread what we were describing, simplified.  You keep thinking of photons as "little bullets," which they aren't.
 

Offline simplified

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Re: Photons and Special Theory of Relativity ?
« Reply #30 on: 02/01/2012 18:29:17 »
I suggest you reread what we were describing, simplified.  You keep thinking of photons as "little bullets," which they aren't.
If we do not know height of photon wave then what creates an eclipse? Diameter of the Moon (parallel to a way of a photon) or diameter of the Moon (perpendicular to way of  photon)? :-\
 

Offline JP

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Re: Photons and Special Theory of Relativity ?
« Reply #31 on: 02/01/2012 18:37:09 »
I'm not an expert on QED, so I can't go into too much detail on photons, but they're derived by looking at what are called plane waves.  Plane waves extend over all space, so they aren't little bullets.  A plane wave in itself might not be particularly physical (after all an infinitely wide and long wave isn't coming out of the sun), but by writing a combination of plane waves, you can generate physical sources, such as the sun.  Similarly, photons don't have simple bullet-like trajectories that you can trace from the sun to the earth, but the combination of many photons acting together does generate these trajectories. 

Its weird and nonintuitive, but that's quantum mechanics.
 

Offline simplified

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Re: Photons and Special Theory of Relativity ?
« Reply #32 on: 02/01/2012 18:58:58 »
The simple question is too complex(difficult) for the backward science. :D
 

Offline JP

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Re: Photons and Special Theory of Relativity ?
« Reply #33 on: 02/01/2012 21:25:47 »
The simple question is too complex(difficult) for the backward science. :D

Nope.  But if you aren't willing to put effort into understanding it, it's not worth trying to explain it further!  *<;o)
 

Offline Phractality

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Re: Photons and Special Theory of Relativity ?
« Reply #34 on: 02/01/2012 23:59:22 »
If photons travel at the speed of light, a clock in a photon shall be stand-still. If it is stand-still photon shall not change or undistructable. How this could be explained?
As a moving clock passes a succession of observer's clocks (which are stationary and synchronized in the observers reference frame) the time difference between the moving clock and each successive observer's clock will change. The moving clock's time will advance more slowly than the time on successive observer's clocks.

The closer a clock's relative speed is to the speed of light, relative to the observer's reference frame, the slower that clock appears to be compared to the succession of observer's clocks that it passes. A clock is a mechanism made of matter. Matter cannot move as fast as light. Even if a clock is moving at .99999999999999999999999999999999999999 c relative to an observer, a photon will still pass that clock at the speed of light in the clock's reference frame. It doesn't even matter which dirction the photon is moving in the clock's reference frame, the speed of the photon is always the same. So it makes no sense to talk about a clock moving along with a photon. The speed of the photon is always the same relative to any clock.
 

Offline LetoII

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Re: Photons and Special Theory of Relativity ?
« Reply #35 on: 18/01/2012 04:09:09 »
i think its not an ultimate standstill, its a different level of speed hard to imagine for us humans. for now
 

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Re: Photons and Special Theory of Relativity ?
« Reply #35 on: 18/01/2012 04:09:09 »

 

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