Is it Possible for a Photon to Be at Rest?

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Discussion Overview

The discussion revolves around the question of whether a photon can be at rest, exploring concepts related to the nature of photons, their speed, and the implications of special relativity. Participants examine theoretical and conceptual aspects of this topic.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants assert that photons only exist at the speed of light and cannot be at rest.
  • Others mention that a frame at rest will always measure the speed of light as c, indicating that light cannot have a rest frame.
  • One participant suggests that in a specially prepared medium, it might be possible for photons to behave differently, referencing a specific article.
  • Another participant discusses the creation of mass from energy when high-energy photons interact, noting that this mass is not connected to the original photons.
  • Some participants argue that from a photon's perspective, it is at rest, while from an external perspective, it is moving at light speed, though this claim is challenged by others.
  • A later reply emphasizes that a photon cannot have a frame of reference according to special relativity, stating that transforming to a frame moving at c leads to nonsensical results.

Areas of Agreement / Disagreement

Participants generally disagree on the possibility of a photon being at rest, with some asserting it cannot be at rest while others explore the implications of different frames of reference. The discussion remains unresolved regarding the nuances of photons in various contexts.

Contextual Notes

Limitations include the dependence on definitions of rest and frame of reference, as well as the unresolved implications of photons interacting in different media.

jimbunyard
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These are not facetious questions. Is a photon at rest still a photon? Can a photon be at rest?

Thanks
 
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No, photons only exists at the speed of light. Since the speed of light is absolute, Photons can not be at rest.
 
A frame at rest, aka an inertial frame, will measure the speed of light as c at all times. Light itself cannot have a rest frame.
 
Khashishi said:
In a vacuum, no. But in a specially prepared medium, maybe? http://www.photonics.com/Article.aspx?AID=28520

Very interesting, but the key phrase is " "quantum mechanical magic trick". If two high energy photons come together and create a particle, this particle has NO internal constituents relating to the two photons. So from energy comes mass, but this mass is in no way connected to the two photons. Theoretically, We can move that mass, and slow it down, but this is not the same as slowing down the two photons that created it. Fascinating though!
 
From a photon's perspective, it is at rest, from ours, it is moving extremely fast. It's all about frame of reference, Einstein talks a lot about this stuff in his Special theory of Relativity.
 
Menaus said:
From a photon's perspective, it is at rest, from ours, it is moving extremely fast. It's all about frame of reference, Einstein talks a lot about this stuff in his Special theory of Relativity.

This is not correct. A photon cannot have a frame of reference per SR. Try transforming a frame moving at c to a frame not moving at c. You get nonsense as an answer. It doesn't work because all inertial frames will always measure light as moving at c in a vacuum. Light, per special relativity, is never at rest and cannot have an inertial frame.
 
Drakkith said:
This is not correct. A photon cannot have a frame of reference per SR. Try transforming a frame moving at c to a frame not moving at c. You get nonsense as an answer. It doesn't work because all inertial frames will always measure light as moving at c in a vacuum. Light, per special relativity, is never at rest and cannot have an inertial frame.

You're right, sorry.
 

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