Can Photons Completely Transfer Energy and Momentum to Free Electrons?

AI Thread Summary
The discussion centers on the challenge of proving that a photon cannot fully transfer its energy and momentum to a free electron. Participants are encouraged to establish equations based on the conservation of energy and momentum to analyze the scenario. The assumption is made that the electron starts from a stationary state. The goal is to solve these equations to determine the electron's energy and momentum post-absorption. This exploration aims to clarify the limitations of photon interactions with free electrons.
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how do you prove that it is impossible for a photon to give up all its energy and momentum to a free electron?
 
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Set up the equations for conservation of energy and momentum and try to solve them for the energy and momentum of the electron after the absorption. For simplicity assume that the electron is initially stationary.
 
ok, thanks! ill try that~
 
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