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Black hole compostion

  1. Jan 6, 2005 #1
    How can the atoms of a back hole move if they are a compression of so much mass? Maybe black holes in the absolute zero state. Any thoughts?
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  3. Jan 6, 2005 #2


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    It is a good question, and no one can really answer it because the laws of physics breakdown at the singularity of a black hole. As for an absolute zero matter state? Close. I beleive the right term for matter and such density is called degenerate matter, because the singularity is not at 0K, it can be pretty hot. Temperature relates to pressure and is a function of density. So pressure can pack them tightly to extreme density.

    -Neutron Star are so dense that the electrons and protons in atom as packed to form neutrons. And this isn't even as dense as a black hole!
  4. Jan 6, 2005 #3
    exactly, maybe the black hole is so dense that the atoms cannot move around. So really, absolute zero is the highest temperature you can reach.
  5. Jan 6, 2005 #4


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    Yup, maybe. I was just reading that when atoms enter a strong enough black hole they get torn apart (called spaghettification :surprised ) and when so much strong atomic force (the strong force) is torn apart it results in energy stronger than an atomic bomb. But it must be unexplainable to consider what is happening to the atoms that make up the black hole at the singularity, some pretty crazy stuff that's for sure.
  6. Jan 6, 2005 #5
    if scientists do find someway for an atom to reach absolute zero, maybe the atoms will act like a black hole and we'd all be dead before we know it.
  7. Jan 7, 2005 #6


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    Like DB said, modern physics can't describe the singularity itself very well. But, as a point, there are no atoms there. Anyway, how can the singularity have temperature? Nothing can radiate beyond the event horizon (don't ask me what's going on within the event horizon!)
  8. Jan 8, 2005 #7
    Matter under pressure = heat?
    Heat = particals that are moving?
    Black holes = matter under exstream pressure but too dense to move??

    Me = confused.
  9. Jan 8, 2005 #8
    In this thread, Chronos talks about how black holes lose mass: https://www.physicsforums.com/showthread.php?t=58736

    Now, Phobos, you said:
    Is this not a contradiction?
    I asked this in the other thread but did not get a responce.

    Now, Phobos, you asked:
    I'm talking about absolute zero. We DONT know what happens when we hit absolute zero, just like we dont know what will happen when we reach a singularity. I'm saying that they might be related in that absolute zero is not a temperature but is the coldest and hottest whatever that at the curretn time is indescribable. What state would we reach when atoms are in absolute zero state? Not a solid, liquid, gas, plasma, bose-einstein condensate, fermionic condensate, quark-gluon plasma, but something beyond. Maybe the "atoms" in a singularity are so compact that they stop moving due to the immense force of gravity. Which is called absloute zero
  10. Jan 8, 2005 #9


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    A black hole is the ultimate state of degenerate matter; atoms are disassembled into elementary particles [protons, neutrons, electrons], particles are torn to pieces, and the pieces themselves [e.g., quarks] are presumable mangled into God knows what kind of exotic smear of weidness. We simply do not yet have the theoretical or technological ability to peek into to planck or sub planckian realm. Perhaps nature has too much modesty to reveal her deepest, darkest secrets. But, everybody likes to keep at least one mystery all to themselves. Heck, somebody could replace you if they knew every last thing there was to know about you.

    Guessing wildly, I wouldn't be surprised if matter ultimately collapsed to some sort of frozen energy-like state. Perhaps a simple wave form. We know some sort of matter-energy equivalency state still exists because the thing still gravitates proportionate to the matter it has devoured. Under current thinking, the singularity is not actually a dimensionless point, but, has some finite, albeit miniscule volume. I vote for the planck density as the limit - largely because it would be hard to prove wrong. It is pretty dense. You could pack all the matter in the universe into a volume too small to see at such a density.
  11. Jan 8, 2005 #10
    The theory is, things radiate beyond the horizon due to virtual particle pairs being formed, one beyond the horizon and one which can escape. This is known as Hawking radiation. Although I read that the larger the black hole, the less quickly it evapourates? Microblack holes evapourate very quickly.

    And don't worry about getting to absolute zero with particles, even if they did form a black hole, it would be too weak to affect anything. Who knows, maybe there are mini blackholes commonly everywhere, even in your body, I'm not sure how hard that would be to measure.

    Blackholes, I don't think you can define temperature. At one extreme, you have an infinite density, so the temperature must be infinite.
    But at the other extreme, their is no particle movement, so it is absolute zero.

    It's like dividing zero by zero, it's an undefined quantity, no finite meaning.

    I haven't studied black holes very much, so forgive any errors in the above post.
  12. Jan 8, 2005 #11
    Yes, you both are correct, however, I was trying to say that a black hole and absolute zero is so indescribable that they are similar.
    We dont know anything and I wasn't trying to relate temperature into any of this, just because I said "Absolute Zero." I was trying to imply the obscure relationship between the two. I take back my thought because of what Chronos said.
    This tells me that in a black hole, atoms are "disassembled" and ripped apart. But the absolute zero state, I considered that the atoms are still in tack and have not been torn into quarks.

    However, Chronos, you have yet to answer my question on your statement on the evaporation of a black hole.
  13. Jan 9, 2005 #12


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    Black hole mass is carried off via Hawking radiation. Virtual particle pairs are continuously created in space. Under normal circumstances, they immediately annihilate each other. The event horizon of a black hole is, however, not a normal circumstance. The particle pairs are occasionally separated and one manages to escape as a real particle. The energy required to promote this virtual particle to a real particle is donated by the black hole through quantum effects. The energy [hence mass] 'escapes'. While not entirely accurate, you could look at it as a type quantum tunneling effect. The more precise [and confusing - as Bohr said, if QT doesn't confuse you, you don't understand it] explanation is the particle that falls into the black hole acquires negative energy while the escaping partner acquires positive energy. The negative energy reduces the total energy [mass] of the black hole. Under QT, a particle is permitted to possess negative energy for a very brief period of time - enough time for those right at the event horizon to fall into the black hole.

    Indulge me to add this about the temperature of a black hole. A black hole does have a temperature. Hawking radiation is the temperature of a black hole. It is inversely proportionate to mass. Massive black holes are extremely frigid, but are always at a temperature above absolute zero.
  14. Jan 12, 2005 #13
    So if the mass increses, then the temperature decreases? why is that?
  15. Jan 13, 2005 #14


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    As the size of the event horizon of a black hole gets smaller, it becomes easier for virtual pairs to separate and radiate away energy from the black hole.
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