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What happens to a Black hole when they die?

  1. Apr 17, 2003 #1
    So What happens to a Black Hole when one dies?
    I've heard that they just dissentigrate, collapse, etc.
    What actually does happen to a black hole when it dies?
     
  2. jcsd
  3. Apr 17, 2003 #2

    drag

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    Greetings Rashid !

    Theoreticly, it just disappears in a powerful
    burst of radiation energy. Since the radiation
    is Hawking Radiation no information about the
    "inside" of the BH is revealed in the proccess.

    Live long and prosper.
     
  4. Apr 17, 2003 #3
    Yeah, because I was thinking, if a black hole was to let loose the Hawkin Radiation, would that radiation not fly all over the universe? And, what would be left behind? Would the singularity expand since it had condensed all that matter over the billions of years? Thanks for the reply. =)
     
  5. Apr 17, 2003 #4

    russ_watters

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    Actually you have it backwards. If a black hole disappears, its EVAPORATING, not condensing. There is simply nothing left.
     
  6. Apr 18, 2003 #5
    Now, I always thought that when a black hole collapsed or evaporated all the information inside (could be) released, wouldn't it be impossible for a black hole to evaporate through Hawking radiation, as Hawking radiation always leaves particles inside, while one escapes?
     
  7. Apr 18, 2003 #6

    russ_watters

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    Isn't one a particle and one an anti-particle or virtual particle? I can't remember and I don't have my copy of ABHOT on me.

    I can't remember exactly how it works, but if something emits energy, it MUST be getting less massive because of the equivalence of matter and energy.
     
  8. Apr 18, 2003 #7
    An anti-particle is created outside of the event horizon, while the original particle is on the inside, therefore the inside particle stays and the anti-particle escapes, this continual division of particles would never equal zero.
     
  9. Apr 19, 2003 #8

    drag

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    Greetings !
    Actually both are created outside the event
    horizon as far as I know. Then one is absorbed
    by the BH and the other one sometimes escapes.

    Live long and prosper.
     
  10. Apr 19, 2003 #9

    LURCH

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    But it would, eventually, produce a mass that is less than the Chandrasacre Limit, leaving an object without enough mass to be a black hole. According to Hawking and some others, the universe is not old enough for any black holes to have reached this critical point yet. I would imagine that once this threshold is reached, the black hole would end rather violently. At the center of a black hole is (theoretically) a mass much more dense than a nuetron star, because the structural resistance of atomic nueclei to compression has been overpowered by gravity. Once the force of gravity is no longer strong enough to keep these nuclei "crushed", it seems to me they should begin to expand. This expansion would accelerate rapidly as the expanding matter gets further from the center of gravitational pull.
     
  11. Apr 21, 2003 #10

    Labguy

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    You are mostly right on this except that the Chandrasekhar Limit is for White Dwarf stars. The low limit for a BH is ~3.2 Sm on formatiom. That applies to formation, not disentigration. The BH can radiate away enough energy (mass) and still fall far below 3.2 Sm until it "explodes" as described below.

    Bigger black holes are colder and dimmer than small black holes. The Hawking temperature is inversely proportional to the mass, while the Hawking luminosity is inversely proportional to the square of the mass. Also, not all virtual particles/antiparticles will "split" with one escaping and the other falling back in. In some cases, mutual annihilation will occur outside the event horizon and the total mass will be lost. From the above, we can see that the BH radiates more rapidly as it gets smaller, and the mass-loss increases until the last of it is radiated away (mostly gamma ray), with the last of the matter radiating so rapidly that the result would appear as an explosion.
     
  12. Apr 23, 2003 #11
    if steven is correct
    the end result is a NAKED singularity
    and thats something we just donot understand
     
  13. Apr 24, 2003 #12
    LURCH...

    Might the above not describe the "end" of THIS INCARNATION of the UNIVERSE...Everything collapsing into a singularity that bursts forth into ANOTHER "Big Bang"??

    I think all the Black Holes will eventually "hook up" and everything will collapse into a singularity AGAIN.

    And/Or Dark Energy will cause the Universe to expand to a point where It is cool enough for a PHASE TRANSITION whereby Dark Energy becomes Dark Matter (or something...just as "matter" "condensed out of" the energy of the "Primal Singularity" right after the Big Bang).

    I think GRAVITY will have the last word...and that word will be "CRUNCH"!
     
    Last edited: Apr 24, 2003
  14. Apr 25, 2003 #13
    What happens when the increasing charge density of gravitational collapse causes the electronic energy to approach surpassing the local rest energy of that quark soup, i. e., when the average charge-charge radius might go beneath that of a corresponding electronic black hole? Is the electronic black hole a quantum limit to black hole structure?
     
  15. Apr 25, 2003 #14

    Perhaps.
     
  16. May 5, 2003 #15
    Just some questions i need answered

    I never knew that black holes could actually die, because aren't they usually made up of a large amount of gravity? but where does the gravity acutally come from? Is it because there's acutally magnetic fields within these black holes, or maybe there's acutally "negative mass" in these things?
    I know questions like these probably seem awkward and strange but I'm still a child trying to figure things out and trying to get my questions answered. So i'll really appreciate it if u can provide me some info in terms that I can understand.

    But how exactly do black holes die out? Because the Black Holes are actually absorbing things while they're around, doesn't this prove the theory that our universe is flat false? I also remember reading from somewhere that within the black holes there is no such thing as time, why is that?
     
  17. May 5, 2003 #16

    russ_watters

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    Re: Just some questions i need answered

    Well, you have a lot of questions here that have been addressed already, but to sum up:

    -Black holes are made of ordinary matter, highly compressed
    -Gravity is a property of mass (which is why you weigh 6x as much on the earth as on the moon - the moon has less mass).
    -Black holes die out because of a complex process where they radiate energy - and energy is a transformation of matter.
    -Black holes do not necessarily absorb everything around them - especially if there is nothing around them to absorb.
    -Since time varies and is slowed down by gravity, when gravity gets strong enough, time stops.
     
  18. May 8, 2003 #17
    Re: Re: Just some questions i need answered

    hahaha, i'm sorry, but i'm new to this website. So far..i've only been a member for 7 days, but i only logged on like 3 times hehe well thanks for summing it up. hehe
     
  19. Mar 7, 2009 #18
    what if the point of singularity of a black hole is the creation of smaller "big bangs" which create other universes. When a black hole "dies", what if it were the creation of a big bang simultaneously to create a new universe. What if the "big bang" was a creation of a the death of a massive black hole. I mean we don't know if our universe isn't apart of a much bigger system. Who knows, maybe there are more universes too.
     
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