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Old 18th September 2014, 04:08 PM   #27
wogoga
Critical Thinker
 
Join Date: Apr 2007
Posts: 334
Originally Posted by Ziggurat in #26 View Post
First off, I'm not arguing that photons do not interact. Secondly, in regards to aligning their propagation direction, we know that this cannot happen because it would violate momentum and/or energy conservation.

The objection that propagation alignment of photons violates momentum and /or energy conservation is indeed serious. The bigger the changing angles, the more convincing the objection.

Let us assume that two photons with each the same energy E are close to one another, and that the angle between their propagation directions is 120. If they want to move in the same direction, then each photon has to change its direction by 60 into the new intermediate propagation direction.

Because of symmetry, the two photons cannot exchange energy, and propagation speed is always c. Before propagation alignment, combined momentum in the new direction:
2 * E/c^2 * 0.5 c = E/c
The factor 0.5 is the result of cos 60. After alignment, momentum in this new direction:
2 * E/c^2 * c = 2 E/c
Therefore, combined momentum in the new direction would double during propagation alignment.

This problem can be solved by a simple ad-hoc-hypothesis. During alignment, radiation (in the form of one or more photons) with energy 0.5 E is emitted in the direction opposite to the new propagation direction, and each of the original two photons loses 25% of its energy E. Then total momentum in the new direction will be again:
2 * 0.75 E/c 0.5 E/c = E/c
As seen from two such photons:
The attempt not to drift apart leads by momentum conservation to an attempt to reduce propagation speed. There are only two solutions: either to give up the attempt to align propagation direction, or to gain forward momentum by emitting radiation backwards.
In any case, the momentum-compensation hypothesis for aligning photons implies:
  • Overall redshift for the interacting photons
  • Release of low-frequency radiation (lost in background)
Cheers, Wolfgang
Simple statistical behavior can be the result of complex individual behavior
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