Explaining Photon Coming to Rest in Relativity Problem

[mritunjay]

Homework Statement

according to theory of relativity anything which travels at the speed of light, can't be slowed down at the speed lower than light speed.So, what happens when photon is absorbed by an electron?In this situation photon comes to rest. How it can be explained?

Homework Equations

The Attempt at a Solution

 

[Doc Al]

In this situation photon comes to rest.

Does it?

 

[Meir Achuz]

according to theory of relativity anything which travels at the speed of light, can't be slowed down at the speed lower than light speed.

Who sez? Photons slow down in glass.

 

[Doc Al]

Photons slow down in glass.

Read the FAQ article: https://www.physicsforums.com/showpost.php?p=899393&postcount=4"