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Black holes and time

  1. Sep 8, 2010 #1
    hello, im new to this forum so im not sure if this is the right spot for me to post my idea, but here it is. :smile:

    i was talking to a friend about differnt questions about how things work when he asked the fallowing question: "is it possible to creat a bubble where time completely stops?" i told him i didint think so, so i tried to explain why when a thought came to me. it was of black holes. from what i have heard on tv and what i have read about black holes, the closer you get to them, the slower time goes. this is because of gravity getting stronger correct? so since the black hole itself is of infinite gravity, does that mean that where the black hole itself is, time would stop? if this is so, when something would enter into a black hole, it would not be expelled as radiation, it would be frozen in time in the black hole. if this is true, this would also mean that black holes would expand right? everything would keep piling on top of everything else. everything that is added on would then increase the gravity and expand the time difference. it would also explain why light cant escape. it couldnt advance because it is frozen in time.

    again im new to this so some of this info might be off, but is this possible?:shy::confused::smile:
  2. jcsd
  3. Sep 8, 2010 #2
    time stops at the event horizon and gravity isnt even infinite there
  4. Sep 8, 2010 #3
    what do you mean?
  5. Sep 8, 2010 #4
    what do you mean 'what you you mean'?
    I mean exactly what I mean.
  6. Sep 8, 2010 #5
    how can gravity stop being infinate? are you saying that gravity doesnt exist in a black hole? that doesnt make sense.
  7. Sep 8, 2010 #6
    the gravity at the event horizon isnt infinite
    it would only be infinite at the singularity
  8. Sep 8, 2010 #7
    why would the gravity not be infinate at the event horizon? also, whats the difference between a singularaty and a black hole? arnt they basicly the same thing?
    sorry if these are stupid questions, im still in school : )
  9. Sep 8, 2010 #8
    gravity follows an inverse square law does it not?
    1/02=infinity so its infinite at the singularity
    1=r2 for r>0 is not infinite
  10. Sep 8, 2010 #9
    can you tell me what each part of the equasion means? what each number represents and each letter? again im in school, i dont know much about the equations.
  11. Sep 8, 2010 #10
    it means that the further you are away from a massive body the less its gravity effects you.
  12. Sep 8, 2010 #11
    so the area around the black hole has the infinate gravity? is that what you mean?
  13. Sep 8, 2010 #12
    gravity is only infinite at exactly the center point of the black hole. At the very singularity itself.

    the singularity is infinitely small.

    how old are you
    what grade are you in
  14. Sep 8, 2010 #13
    wait, so does that mean my idea is possible?
  15. Sep 8, 2010 #14
    im a sophmore in high school
  16. Sep 8, 2010 #15
    i think i might have missunderstude something. i got a lot of this info off of the show through the wormwhole. the part im not sure about is the debate between stephen hawking and that plumber guy (cant remember his name). stephen hawking said at first that information was destroyed by blackholes, but the plumber guy proved him wrong by saying that it was expelled as radiation (i think). the idea of what i am saying is that since the info would be stoped in time, it wouldnt be given off as radiation as this guy said. im not sure if this is right though.
  17. Sep 11, 2010 #16
  18. Sep 12, 2010 #17


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    Gravity is clearly not infinite at the event horizon. And if it were infinitely strong at the singularity, how would it diminish over distance? This paradox is easily resolved if the singularity has a finite volume, however tiny.
    Last edited: Sep 12, 2010
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