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Other sizes for black holes

  1. Jul 5, 2011 #1
    I have read that it is possible that primordial black holes could have formed in many different sizes, from micro black holes to hundreds of solar masses, my question is this.
    What is the smallest black hole that could survive from this time until now, without being destroyed by hawking radiation, and would it be small enough that we could perform experiments on it that we would not be able to perform on the much larger black holes (those above the chandresekhar limit)
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  3. Jul 5, 2011 #2


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    for an elementary treatment. The answer is a bit less than 10^12 kilograms.

    Here is peer reviewed reference quoting Hawking at the beginning with a similar figure for minimum mass for a surviving primordial black hole:

    Last edited by a moderator: Apr 26, 2017
  4. Jul 6, 2011 #3


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    Well, our best bet for detecting these things is through their evaporation. Some people think they may see a teeny tiny signature in current gamma ray bursts that could be primordial black holes, but the evidence looks pretty sketchy to me so far:
  5. Jul 26, 2011 #4
    I saw some recent black hole news involving water vapour!

    Black hole sucks in 140 trillion times the world's oceans:

    http://news.yahoo.com/black-hole-sucks-140-trillion-times-worlds-oceans-163503124.html [Broken]
    Last edited by a moderator: May 5, 2017
  6. Jul 29, 2011 #5


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    I think I have to go to the bathroom after reading that.
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  7. Jul 29, 2011 #6
    Regarding Tanelorn's Yahoo article, I did locate the Jet Propulsion Laboratory's article, Astronomers Find Largest, Most Distant Reservoir of Water, dated July 22, 2011:

    "Quasar Drenched in Water Vapor
    This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view."

    It appears that Astrobiology also covered the subject matter:
    Galactic Ocean of Water Vapor Encircles a Black Hole

    Very fascinating information.:smile:
    Last edited: Jul 29, 2011
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