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Black Holes vs wormholes

  1. Apr 12, 2003 #1
    [SOLVED] Black Holes vs wormholes

    when a planet has a black hole outside its orbit. and you were on the surface. would time slow down as the black hole gets closer? because the black hole is pulling everything towards it. i know nothing can escape a black hole, not even light. As we know wormholes are theorectical, we can predict the motion, speed and velocity by giving examples using laws of physics. do wormholes pull things towards it as like a black hole or is it totally different effect ( speaking theoreactlly)? any laws of physics showing the calculations of examples by how much time would slow down with the current data known of black holes would be much apprecated.
  2. jcsd
  3. Apr 12, 2003 #2
    Where is the object you wish to measure time relative to - towards the hole, or away from it? The denser (or more attenuated) intervening spacetime becomes, the longer (or shorter) the interval of time elapsed. Light can, by quantum effect, escape the horizon of the black hole by a process called Hawking radiation. Wormholes, having progressively reduced curvature at first, do attract gravitationally with their cylindrical symmetry, but not as greatly as the spherically collapsed black hole.
  4. Apr 12, 2003 #3
    when an object is going towards it, time must slow down some way. i thought a black hole's gravtational field was so strong nothing could escape it? does hawking's radiation prove that light can escape from the event horizon?.
  5. Apr 16, 2003 #4
    Hawking radiation makes black holes glow slightly with photons, neutrinos, and other massive particles.

    This is due to virtual particle pairs being created near the event horizon of the black hole. This happens everywhere as particle-antiparticle pairs, which upon creation annihilate each other; although, near the event horizon it is possible for one to fall in before annihilation and the other particle to escape, as Hawking radiation.

    This does mean light escapes from the event horizon, part of it, although the hawking radiation never actually enters the event horizon. Hawking radiation also allows for black holes to lose mass, and possibly 'evaporate' (or decay).

    Time slows down as the black hole approaches, or you approach the black hole, only relative to you, as viewed by an outside observer. You would notice no time change. If you entered the black hole and stayed for 10 years, and then exited the black hole, then you would have only aged 10 years, whereas everybody 'outside' of the black hole would have aged more then 10 years.

    You seem to think there is a 'universal' time everywhere in the universe by which "TIME" is gauged, this is not so.
    Last edited: Apr 16, 2003
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