Frame dragging from a light beam

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Discussion Overview

The discussion revolves around whether a light beam creates linear frame dragging around it and the implications of this on the behavior of light as it travels through the universe. The conversation touches on theoretical aspects of general relativity and the nature of gravity as influenced by energy and momentum.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions if a light beam creates linear frame dragging, suggesting that if it does, light might become 'tired' due to momentum exchange with the environment.
  • Another participant argues that frame dragging is a consequence of moving mass objects and posits that photons do not qualify as such, though they acknowledge the possibility of being incorrect.
  • A different participant asserts that rotating black holes create frame dragging and argues that photons could contribute to frame dragging from the beginning, even before forming a black hole.
  • One participant discusses the distinction between Newtonian gravity and general relativity, emphasizing that the stress-energy tensor, which includes momentum and energy, affects the curvature of space-time, suggesting that light can indeed cause gravity and potentially frame dragging.
  • A later reply requests a calculation to determine if light can cause frame dragging, expressing concern that if the answer is affirmative, it implies light must become 'tired'.

Areas of Agreement / Disagreement

Participants express differing views on whether light can cause frame dragging, with some supporting the idea and others contesting it. The discussion remains unresolved with multiple competing perspectives present.

Contextual Notes

The discussion includes assumptions about the nature of mass and energy in relation to gravity, and the implications of the stress-energy tensor in general relativity. There are unresolved mathematical aspects regarding the calculation of frame dragging by light.

Dmitry67
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Does light beam create linear frame fragging around it?
If answer is positive, can light become 'tired' going thru the universe and exchanging the momentum with the environment via frame dragging?
 
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Just my 2-cents:
I think frame-dragging is a potential consequence of moving mass objects, of which a photon would not qualify.
Could be wrong.
 
Hm... I doubt it.

1. We know that rotating black holes create frame dragging.
2. Based on the 'no hair' theorem it is irrelevant what BH is made of.
3. If could be made of photon gas, for example.
4. Frame dragging can not 'switch on' instantaneously when photon gas cloud became a BH
5. So there was a frame dragging from a very beginning, from the photons.
 
The idea that mass causes gravity is a Newtonian idea. While it's perfectly correct in Newtonian theory, it's not correct in GR. In GR, it's the stress energy tensor that causes gravity. Saying the words "Stress-energy tensor" unfortunately might scare or confuse someone who hasn't studied the theory, but what it means is that anything that has momentum and energy can affect the curvature of space-time. Light certainly has both momentum and energy and thus it can and does affect the curvature of space-time - i.e. cause "gravity".

As far as to the question whether or not light specifically can cause frame dragging, I believe the answer is almost certainly yes, but I haven't calculated it personally.
 
pervect, I googled it a lot, but I did not find an answer.
Could you calculate it?
Because if nswer is YES then light MUST become 'tired'.
 

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