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Micro Black holes

  1. Sep 14, 2007 #1
    Mini black holes have been postulated to exist at the realm of sub-atomic particles. What effect would these micro black holes have on other sub atomic particles? Also, apparently, the mass of one of these mini black holes is the same as mount everest (or some other large mountain)
  2. jcsd
  3. Sep 14, 2007 #2


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    That seems like a right good order of magnitude first guess, Kurt.

    To check it you could take the COMPTON WAVELENGTH of a proton. This is a typical idea of the "size" of a particle.

    And you could ask for what mass M is the Schwarzschild radius 2GM/c^2 equal to that Compton wavelength.

    You can look up all the constants you need at the NIST website.
    But there is also a quick way.

    you should just always remember that the Planck mass is 13E18 times the proton mass (13 billion billion times)
    that means the proton Compton wavelength is larger than the Plancklength by that same 13E18 factor.

    now I neglect things like pi and factors of 2 and just say that the blackhole mass M must be greater than the Plancklength by the same factor.

    So this Mount Everest mass is found to be simply 13E18 times the Planckmass, which is 21 micrograms.

    So that comes to about 21 x 13E12 grams which is 26E13 grams which is 26E10 kilograms. You can compare that with the mass of Mount Everest any way you like. I think it is about E8 cubic meters of rock. Not quite the size of Everest but roughly same order magnitude.

    The Compton wavelength of a lighter particle like electron is larger. So you need a bigger blackhole which is therefore more massive. So if you want a more impressive mass, go to an electron.

    Other people who don't think in Planck units would have a different idea how to calculate and wouldnt like what I just told you but unless I made some simple mistake in arithmetic that is one possible way.

    these mini blackholes would be VERY HOT and would tend to boil away, according to conventional ideas. so you ask about effect on things around them. I dont even like to speculate. could be very destructive.
    might not last very long. someone else may want to take the time to speculate.

    the real miniblackholes that people like to speculate about are much smaller than an electron or proton and so much less massive than Everest. they don't represent such a dangerous amount of energy. they also evaporate quickly.
    perhaps they are safer and less drastic to think about :smile:
    Last edited: Sep 14, 2007
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