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Visible Universe a fuzzball?

  1. Jun 8, 2012 #1
    Could the edge of the visible universe (13.7 billion light-years, where recession velocity equals light speed), be the radius of an event horizon of a non-classical black hole such as a fuzzball?

    http://en.wikipedia.org/wiki/Fuzzball_(string_theory [Broken])

    "Due to the mass-density inverse-square rule, all fuzzballs need not have unimaginable densities. There are also supermassive black holes, which are found at the center of virtually all galaxies. Sagittarius A*, the black hole at the center of our Milky Way galaxy, is 4.3 million solar masses. If it is actually a fuzzball, it has a mean density that is “only” 51 times that of gold. At 3.9 billion solar masses, near the upper bounds for supermassive black holes, a fuzzball would have a radius of 77 astronomical units—about the same size as the termination shock of our solar system’s heliosphere—and a mean density equal to that of the Earth's atmosphere at sea level (1.2 kg/m3)."

    From this quote, a fuzzball (non-classical black hole) can have a radius of 77au, and have a mean density of 1.2 kg/m^3? Wow, doesn't it seem that there would be no reason for strings in some regions to stay non-condensed, but instead condense into elementary particles? Further, why couldn't there be elements in regions of this space? Even further, why can't there be many smaller fuzzballs inside? Now consider my thread topic. Why not? The mean density of the visible universe could be on par with that found in a fuzzball with the radius of the visible universe.

    Furthermore, consider expansion. Could the reason for expansion be due to infalling matter? Much like what we observe as black holes devour matter surrounding them, if our visible universe is the inside of a fuzzball, then if it's gaining mass, its schwartzchild radius is expanding over time.

    Now consider rapid expansion in the early universe. It could have been caused by the initial beginning of the black hole universe, sucking in its immediate surroundings, undergoing rapid expansion. It has slowed down since--though it's still gaining mass--because it's pulling in more energetic matter that it wasn't able to pull in at the beginning.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Jun 9, 2012 #2

    Simon Bridge

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    Why pick the visible universe limit for the radius? Wouldn't that imply we are in the center? Do you think that someone 13billion ly away will see an edge to the Universe 0.7billion ly away?

    There are a lot of discussions in PF about whether the Universe is inside a BH of one kind or another.


    I think the trick is coming up with an observation that requires the Universe to be inside a fuzzball ...
  4. Jun 9, 2012 #3
    you are absolutely right. I didn't think of that. Kind of makes the idea seem unworkable
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