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Singularity Semantics

  1. May 15, 2008 #1
    It has been claimed that,
    "The singularity of a black hole is not a point in space it is not even a point in spacetime, in fact it is not even in spacetime. The singularity is not a point on the spacetime manifold. If it were it would obviously not be a singularity."
    The source is unimportant.

    I feel that a singularity is technically any location--in space-time--where properties, namely density, become infinite. And less technically, any location that we don't really feel can exist according to the understandings of generally excepted theory (i.e. infinite density again, information loss, blah blah blah).
    Colloquially, a gravitational singularity has become synonymous with black-holes (perhaps unfortunately), in which case a black-hole (the juicy core in particular) very possibly occupies a finite, non-zero, region of space-time.

    Is there any backing to "singularities" not occupying space-time?
    If this is the case, how can they come into existence, and later(temporally) cease to exist?
    How can they interact with space-time?

  2. jcsd
  3. May 15, 2008 #2
    Hi Iskelley,

    Most textbooks regard a black hole as a point singularity. That is one conclusion drawn from general relativity (that Einstien did not agree with) but there are other alternatives that interpret the conclusions of GR differently. If you want to the explore them you can start at the wikipedia article titled "Nonsingular black hole models" here http://en.wikipedia.org/wiki/Nonsingular_black_hole_models and perhaps also refer to post#32 of the "Gravitational Redshift" thread here: https://www.physicsforums.com/showthread.php?t=234292&page=3
    Last edited by a moderator: Apr 23, 2017
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