Is it Possible for a Photon to Be at Rest?

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Photons cannot be at rest, as they always travel at the speed of light in a vacuum, which is an absolute constant. The concept of a rest frame for a photon is nonsensical according to special relativity, as all inertial frames measure light as moving at speed c. While photons can interact to create particles with mass, this mass is not related to the photons' state of motion. The discussion highlights the importance of frame of reference in understanding the behavior of light. Ultimately, photons exist only in motion and cannot have a rest state.
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These are not facetious questions. Is a photon at rest still a photon? Can a photon be at rest?

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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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