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B Particles touching each other inside a Black Hole's core...

  1. Nov 2, 2016 #1
    I had a quick question regarding particles touching each other. I know no one can really say for sure but inside a black hole where the gravity is astronomical would the particles be considered to be pressed up against each other? are the forces involved enough to compress atoms down in to the physical size of the particles they consist of and in such a state could 2 atoms actually touch /connect? would this create a super atom?

    Last edited by a moderator: Nov 2, 2016
  2. jcsd
  3. Nov 2, 2016 #2

    Jonathan Scott

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    The concept of particles "touching" is not very meaningful, as they are not like little balls.

    A neutron star consists mostly of neutrons packed together even closer than in the nucleus of an atom, so in that sense it can be considered like being made into a "super atom".

    However, a black hole is something entirely different, where space and time have effectively given way completely. Anything which falls into it disappears into a mathematical singularity, which at present is outside the scope of known physics.
  4. Nov 2, 2016 #3
    Thanks for the reply, I guess I was defining particles such as neutrons and protons as like little balls, as they are what give the atom mass. - My mistake.

    As for the blackhole, could it be described of having all that mass it has swallowed up compacted down like a neutron star but much denser. So all of the atoms are compressed together? I know the maths will describe this as a singularity. But in reality we can never know, but could it be seen in this sense. Instead of describing a black hole as anymore special than a neutron star. I am trying to imagine a point where all of that mass doesn't just simple vanish from our universe and is infact still there .

  5. Nov 2, 2016 #4

    Jonathan Scott

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    Unfortunately, it definitely doesn't make sense to describe a black hole as being made of anything like atoms or any other particles. The mass is still there as part of the overall object, but once anything is behind the event horizon it doesn't make sense to try to describe it in any normal terms.

    And curiously, the nearest thing we have to "density" for a black hole actually gets less the larger the black hole (as the circumference of the event horizon is proportional to the mass).
  6. Nov 2, 2016 #5


    Staff: Mentor

    I understand what you say by what about this scenario?

    We keep adding neutrons to a neutron star one at a time. At some point the neutron start is so massive and bends spacetime so much that almost nothing could escape. Add one more neutron, and it becomes a BH. Instead of "almost nothing", now "nothing " can escape. But are there other drastic differences that we can be certain of that make it entirely different?

    We can only speculate about what happens to the contents of the interior of the BH. Some models predict a singularity, but we can never confirm that, as far as I know.
  7. Nov 2, 2016 #6

    Jonathan Scott

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    A black hole is a theoretical prediction of General Relativity with specific properties. So far, we know that most observations seem to support their existence and there is clear evidence of extremely massive dense objects which would have to be black holes if GR is correct at that level. So we are discussing a theoretical model. However, the mathematical nature of the singularity cannot be described by known physics.

    It is thought that neutron star collapse to a black hole is likely to occur at some point when the gravitational pressure overcomes the neutron degeneracy pressure so the collapse starts before the black hole occurs, and it then effectively becomes a black hole loosely speaking when the rate of collapse reaches the speed of light. However, this is not known for certain.
    Last edited: Nov 2, 2016
  8. Nov 2, 2016 #7
    I have always pictured the event horizon (for light) as a sort of bubble, at this point space is warped enough that light cannot escape, this is out outer circumference of the black hole but in reality all of the light and particles still spirals into a single point on the inside of the event horizon. As you say it doesn't make sense to describe it in normal terms but the particles haven't changed so it makes perfect sense to consider them in there normal state. Albeit a bit squashed and stretched etc.

    Back to the original question the particles must "touch" or collide with each other as they do in a particle accelerator perhaps, is there a physical interaction when they collide? Could the singularity be a ball of the stuff that makes up all of the particles that have fallen into it?
  9. Nov 2, 2016 #8

    Jonathan Scott

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    What happens at the singularity is unfortunately outside the scope of current physics. There is speculation that it must be influenced by quantum theory, but no mainline theory. There is general agreement however that particle properties are completely irrelevant inside the black hole.

    Particles are described by wave functions which are localized in space but do not have hard limits. They interact by the various different forms of force. For particles which bind together, the forces are attractive until the particles are very close together and become repulsive if they get any closer, so that is similar to touch, which is how we describe that on the macroscopic scale for electromagnetic forces.

    The physics of the singularity as described in General Relativity is undefined. It basically involves zero divided by zero or infinity divided by infinity (or both). Current physics cannot be extended to the singularity without producing contradictions.
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