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Erik Verlinde's paper on Emergent Entropy

  1. Apr 27, 2014 #1
    There is one paragraph that says:
    Our starting assumption is directly motivated by Bekenstein's original thought experiment
    from which he obtained is famous entropy formula. He considered a particle with
    mass m attached to a ctitious "string" that is lowered towards a black hole. Just
    before the horizon the particle is dropped in. Due to the in nite redshift the mass
    increase of the black hole can be made arbitrarily small, classically. If one would take a
    thermal gas of particles, this fact would lead to problems with the second law of thermodynamics.
    Bekenstein solved this by arguing that when a particle is one Compton
    wavelength from the horizon, it is considered to be part of the black hole. Therefore,
    it increases the mass and horizon area by a small amount, which he identi ed with one
    bit of information. This lead him to his area law for the black hole entropy."

    I don't quite understand what he meant when he gave the thermal gas example. How does it lead to problems with the second law of thermodynamics?

    Also how exactly does a particle being a Compton of wavelength away from the horizon (so as becoming part of the black hole) solve the problem?
  2. jcsd
  3. Apr 27, 2014 #2


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    you have to read Bekenstein's original paper listed in the references.
  4. Apr 28, 2014 #3
    I was hoping I get some help just concerning this very idea without getting to read the whole paper from whom are familiar with this.
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