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Negative acceleration

  1. Apr 6, 2008 #1
    Negative acceleration....

    I am not to sure if anyone knows this and I am sure this is testing a physicists' best mettle...so here goes. When you are experiencing free fall upon entering a black hole...at the peak of the vortex or at some prior to singularity, wouldn't you be experiencing negative acceleration...?:rofl:
  2. jcsd
  3. Apr 7, 2008 #2
    You mean you must start to accelerate in a direction away from the singularity because you must come to a stop at the singularity?

    As I understand it there's no reason for this to happen, because you (or the particles you're made of) will only experience a finite amount of time, so you can continue to accelerate towards the singularity, and you don't exist after you hit it.
  4. Apr 7, 2008 #3
    That's the problem though, the time you speak of is not in terms of the 'time' we understand it to be. It's not an experiential process as we know it to be.
    I think what I am trying to understand is that there is no meaningful accerleration towards singularity but a negative acceleration that occurs prior to the point of singularity. There is no stoppage but a constant continuum of matter
  5. Apr 7, 2008 #4


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    There is no problem with the concept of "time". Proper time will continue to be defined, so for an observer falling toward the singularity he can just keep looking at his watch without problem (ignoring the fact that the watch gets stretched beyond factory tested limits).
  6. Apr 7, 2008 #5
    while talking about a blackhole we consider a centrifuge in the place of a blackhole. as u knw dat an object at the extreme end or at the circumference of the centrifuge experiencees maximum accleration. its accleration reduces as the object falls in ! so at the centre the accleration is zero. hence we can get retardation !(negative accleration )
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