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Black Hole Questions

  1. Jun 28, 2009 #1
    Have any papers been published concerning BH's on membranes (superstring) vs non-string universe? My questions are:

    1. if we have a membranous universe/dimension then all angles of approach to a BH lead to its critical circumference so you cannot sneak up on it so to speak.
    = Questions: (a) there is a BH throat: (b) how long must it be? (c) any slope defined of diminishing size? (d) Does spin continue all the way down or would "final gravity strength" at some point straighten out any gravitational or magnetic lines from swirling? (e) If our singularity empties into another universe/dimension are we intruding another universe/dimension into one already extant (ramifications?) or is it, as it enters, one tiny BH that explodes with no consequence to the intruded-into universe/dimension (like the early Big Bang mini-BH's)?

    2.That conversely might say that if the universe is not membranous, then the BH must have a spherical shape which says the singularity is a core and therefore the BH is like a planetary body with its entire surface being a horizon and the entire body may or may not shrink. Is there a backside you might say. Anyone published on the 360 degree-ness of a black hole or not?

    Any of these types of questions been researched? I can find nothing.
  2. jcsd
  3. Jun 30, 2009 #2
    how would the 2 surmises be expressed mathematically and to what would implications point (regardless of some obvious leavings-out of question 2)?
  4. Jul 1, 2009 #3
    I can't answer your question directly, but Leonard Susskind gave a talk in NJ at Rutgers in 1993 where he explained how a black hole can be represented as a tangled ball of string. This view sees such a string as flattened out on the horizon with bumps in the string due to jitters becoming particles that are emitted as Hawking radiation. not that far from a "brane" but he did not use that word in his recent book.

    Ashoke Sen, the Indian physicst also produced related papers about that time involving extremal black holes where charge and gravity are perfectly balanced, and Cumrum Vafa, the Iranian born theorist, also produced related work.

    The above is recounted in Leonard Susskind's 2008 book THE BLACK HOLE WAR Chapter 21, Counting Black Holes.....I happened to read the chapter a few days ago...
  5. Jul 1, 2009 #4
    I'll have to check in on Susskind's 2008 book. Although using the 1993 term "ball" still leaves my seemingly easy question #2 standing and I bet a lot of his string thoughts from '93 are, of course, quite different in 2008. Of course, the obvious thing of Hawking's Radiation on a tangled ball would be 360 radiation instead of horizon's circumferential radiation plus "tangled" means bumps and those go away at critical circumference. But thats his old '93 stuff so irrelevant
    Still interested in the questions I posed tho and what an equational view of it could point to or not.
  6. Jul 2, 2009 #5
    Turns out I found a better lead in Susskinds book: Cumrun Vafa and Andy Strominger in 1996 constructed an extremal balck hole with strings and D branes. Within a few weeks Juan Maldacena at the time a student at Princeton and his thesis advisor Curt Callan produced a paper with similar results but different methods combining D1,D5 branes and strings...Because this is a 2008 book I would hope that if anything significant occured since those papers he would have mentioned it...unless those advances had little to do with the topics in his book....
    Anyway, with the general subject,authors and approximate date, arXiv might yield some papers....I've never searched it though so maybe some experts here can guide you...
    Last edited: Jul 2, 2009
  7. Jul 2, 2009 #6
    Down Barnes and Noble today then Naty. Thanks for the book lead which should be interesting even if it does not directly address my directional question.
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