Does the Compton Effect Challenge the Particle Nature of Light?

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    Compton effect
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Discussion Overview

The discussion revolves around the Compton effect and its implications for the particle nature of light, particularly in relation to the photoelectric effect. Participants explore the conditions under which photons interact with electrons, the conservation of energy and momentum, and the distinctions between the two phenomena.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant expresses confusion regarding the Compton effect, suggesting it seems to violate the particle nature of light as described by the photoelectric effect.
  • Another participant clarifies that the Compton effect involves a photon interacting with a free electron, not an electron bound in an atom.
  • A different participant points out that the photoelectric effect allows for the complete absorption of photon energy, which is not the case in the Compton effect due to the need for energy and momentum conservation.
  • Some participants emphasize that the photoelectric effect involves a collective recoil of a metal piece, not just a single atom, when an electron is ejected.
  • One participant notes that light interference also poses challenges to the particle nature of light and suggests that quantum electrodynamics provides a more accurate description of light-electron interactions.
  • There is a suggestion that the original poster may be conflating the Compton effect with the photoelectric effect and should specify the context involving a metal.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as there are multiple competing views regarding the nature of the Compton effect and its relationship to the photoelectric effect. Some participants argue for the distinctions between the two effects, while others raise questions about the implications for the particle nature of light.

Contextual Notes

Participants highlight the importance of distinguishing between free electrons and bound electrons in atoms, as well as the roles of energy and momentum conservation in both the Compton and photoelectric effects. There is also mention of the historical context of experiments involving metals.

Sudarsan
I have a problem on Compton effect..
Its told that, when a incident photon of frequency 'v' strikes an atom, there is a ejection of an electron and there is photon ejeted out with lesser frequency...

But, the above mentioned seems to violate particle nature of the light and photo electric equations, as its said that if the incident photon hits the electron, if it has energy more than work function the electron get ejected and remaining energy is used as kinetic energy for the electron. If the energy is not equal to the work function then the electron get excited and return back to its ground state by emmiting a photon with same frequency as that of the incident photon.

Whereas in compton shift both condition occurs at same time with incident of one photon...
Is it possible??
does it have any other explanations??

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The Compton effect describes the interaction of a photon and a free electron, not an electron in an atom. Because it is necessary to conserve both energy and momentum, it is not possible for all of the incoming photon energy to be absorbed.
 
Sudarsan said:
I have a problem on Compton effect..

As @phyzguy has pointed out, what you are describing is not the Compton effect, since that involves free electrons. It looks like what you are describing is actually the photoelectric effect. In the photoelectric effect, the rest of the atom recoils, so energy and momentum can both be conserved even though the incoming photon is fully absorbed.
 
PeterDonis said:
In the photoelectric effect, the rest of the atom recoils, so energy and momentum can both be conserved even though the incoming photon is fully absorbed.
In the photoelectric effect, not just a single atom is involved, but rather a large bound collection of atoms (piece of metal) from which the electron is ejected.
 
jtbell said:
In the photoelectric effect, not just a single atom is involved, but rather a large bound collection of atoms (piece of metal) from which the electron is ejected.

Yes, good point, the recoil is not just one atom, it's the whole piece of metal. (And the electron that gets ejected was not bound to just one atom, but to the whole piece of metal.)
 
Of course, you can have the photoeffect also on a single atom, but indeed the usual (and historical) setup is to use a metal plate.
 
First, I draw your attention that light interference also violates particle nature of light. Excuse me, interaction of light with electrons is usually described by equations of quantum electrodynamics but not by words.
 
You probably talking about photoelectric effect, not Compton effect, and hence you must specify a metal.
 

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