Motion of light in a gravitational field

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Discussion Overview

The discussion revolves around the motion of light in a gravitational field, specifically examining whether light follows a cycloidal path or a brachistochrone path according to the principle of least time. The conversation touches on theoretical implications and interpretations of light's behavior in gravitational contexts.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that light follows a cycloidal path in a gravitational field based on the principle of least time.
  • Others argue that the correct term should be brachistochrone, which refers to the path of least time for a particle under gravity.
  • A participant questions what the brachistochrone would be in the context of light's motion.
  • One participant clarifies that while the brachistochrone is the quickest path for a massive object starting from rest, light's initial velocity and direction affect its path.

Areas of Agreement / Disagreement

Participants express disagreement regarding whether light follows a cycloidal path or a brachistochrone path, indicating that multiple competing views remain without a consensus.

Contextual Notes

The discussion includes assumptions about initial conditions and the definitions of paths in gravitational fields, which remain unresolved.

khil_phys
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Would it be correct to say that light follows a cycloidal path in the presence of a gravitaitonal field, in accordance with the principle of least time?
 
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Hi Khil_phys
Why cycloidal ? don't you mean brachistochronic ?
 
I did mean brachistochronic. What will be that brachistochrone?
 
khil_phys said:
Would it be correct to say that light follows a cycloidal path in the presence of a gravitaitonal field, in accordance with the principle of least time?
No. The brachistochrone is quickest path in gravity for a massive object with zero initial velocity. But light already has an initial velocity, and the path is dependent on its initial direction.
 
Thank you :)
 
oli4 said:
http://en.wikipedia.org/wiki/Brachis...is_the_cycloid[/QUOTE]

Thank you A.T. :)
 
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