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CWK
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I am currently reading the third edition of Modern Physics by Serway/Moses/Moyer and this quote, in reference to the Compton Effect, seems to conflict with various other online sources I have checked. I understand that the classical description does not give accurate predictions of what actually happens, but I am nonetheless interested in understanding its predictions.
There is also a footnote that says:
A few conflicting sources:
Using the classical wave theory, I would predict that the x-ray would cause the electron to oscillate at the same frequency as the incident radiation, as is stated by the latter two sources. The way I see it, the electric field of the incident radiation would cause the electron to oscillate along the same direction and at the same frequency as the electric field of the incident radiation, and this would in turn allow the magnetic field of the incident radiation to cause the electron to oscillate along the direction of propagation, still at the same frequency as the incident radiation.
I would appreciate it if someone more knowledgeable could inform me on what the classical model predicts and how it predicts that.
... classical theory predicted that incident radiation of frequency ##f_0## should accelerate an electron in the direction of propagation of the incident radiation, and that it should cause forced oscillations of the electron and reradiation at frequency ##f'##, where ##f' \leq f_0##. Also, according to classical theory, the frequency or wavelength of the scattered radiation should depend on the length of time the electron was exposed to the incident radiation as well on the intensity of the incident radiation.
There is also a footnote that says:
This decrease in frequency of the reradiated wave is caused by a double Doppler shift, first because the electron is receding from the incident radiation, and second because the electron is a moving radiator as viewed from the fixed lab frame. See D. Bohm, Quantum Theory, Upper Saddle River, NJ, Prentice-Hall, 1961, p. 35.
A few conflicting sources:
- https://phys.libretexts.org/Bookshelves/University_Physics/Book:_University_Physics_(OpenStax)/Map:_University_Physics_III_-_Optics_and_Modern_Physics_(OpenStax)/06:_Photons_and_Matter_Waves/6.04:_The_Compton_EffectBy classical theory, when an electromagnetic wave is scattered off atoms, the wavelength of the scattered radiation is expected to be the same as the wavelength of the incident radiation.
- https://en.wikipedia.org/wiki/Compton_scatteringAlthough classical electromagnetism predicted that the wavelength of scattered rays should be equal to the initial wavelength,[5] multiple experiments had found that the wavelength of the scattered rays was longer (corresponding to lower energy) than the initial wavelength.
Using the classical wave theory, I would predict that the x-ray would cause the electron to oscillate at the same frequency as the incident radiation, as is stated by the latter two sources. The way I see it, the electric field of the incident radiation would cause the electron to oscillate along the same direction and at the same frequency as the electric field of the incident radiation, and this would in turn allow the magnetic field of the incident radiation to cause the electron to oscillate along the direction of propagation, still at the same frequency as the incident radiation.
I would appreciate it if someone more knowledgeable could inform me on what the classical model predicts and how it predicts that.
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