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Unruh effect = Compton effect ?

  1. Aug 6, 2010 #1
    Unruh (by definition) effect shows that an accelerating observer will observe black-body radiation.
    It is in a gravitational field.

    Compton scattering by definition. The inelastic scattering of photons in matter results in a decrease in energy (increase in wavelength) of an X-ray or gamma ray photon, called the Compton effect. Part of the energy of the X/gamma ray is transferred to a scattering electron, which recoils and is ejected from its atom, and the rest of the energy is taken by the scattered, "degraded" photon.
    It is in an EM field.

    If the the Vacuum (gravitational field) is a plasma of the virtual particle-antiparticle pairs the mechanism of the Unruh and Compton is the same. An accelerating electron in the gravitational field (virtual plasma) absorbs more virtual pairs than emits and does see the thermal bath (the vacuum density increases towards the massive object). An accelerating electron in the EM field absorbs more photons than emits and does see the thermal bath too.
    http://www.hlawiczes1.webpark.pl/gravastar.html [Broken]
    Isn't it ?
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 6, 2010 #2
    The Unruh effect isn't due to the gravitational field. It is an effect in flat space-time.

    The gravitational field isn't the vacuum.
  4. Aug 7, 2010 #3
    The Unruh effect is in an accelerated motion. The gravitational field is an example where we accelerate.
    What is a gravitational field and what is a spacetime. It depends on a theory. If you stop at the pure General Relativity you are right and Unruh effect isn't true.
    It is true if we go deeper into a Quantum Gravity. There are many ideas, of course.
    One of them is the thermodynamic space, where the gravity is an entropic force and you use Unruh effect. You may read about zero point energy http://www.calphysics.org/articles/gravity_arxiv.pdf
    We are in XXI century and there is a progress in physics.
    Last edited: Aug 7, 2010
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