Black holes and entropy: a question

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>>8872871
>Seems to me, there should be a certain density (or heat) at which entropy tears apart sub atomic particles, converting all mass into energy.

>>8872873
Are you trying to say mass cannot be converted into energy?

>>8872873
So why can't entropy convert mass into energy?

The form the mass takes when it converts to energy is the bent spacetime. And time is slowed to a near-standstill beyond the event horizon from our perspective, so the fate of the mass after the horizon forms isn't that important to the black hole characteristics as we observe them from our vantage point in time.

>>8872891
Are you trying to say (and correct me if I'm wrong) that since time stands still by our perspective, that the motion of mass ends once it passes the event horizon, that entropy never increases, heat is never generated, and all motion stops. That the event horizon becomes a shell of all mass striking it the moment it is created because no movement is possible when time is frozen.
Is that what you're saying?

>>8872910
I don't understand how the surface of a black hole carries information yet. I'm reading that chapter in "Black Holes and Time Warps" by Kip Thorne, but I am too busy with school to finish right now. As for the stellar core mass imploding and increasing in entropy that way, yes it's frozen in that process essentially forever from our perspective outside the horizon. The singularity within any black hole can be thought of as having not yet formed at this moment in time from where we are. The horizon informational content is where all the entropy action happens as far as we are concerned out here. I don't get that part yet.

>>8872956
Yeah, I hate mixing perspectives. I try to think in terms of "I am a molecule as I travel to the center of mass".
From that perspective, entropy should destroy me as an atom, then increase until my mass is converted into energy. At some point along the journey, entropy should overwhelm all other forces.
According to my little mind, that is.
>except I'm obviously wrong.

Out of curiosity, if enough concentrated energy can create black holes, what would happen if you tried to concentrate enough black holes into one point? Would that result in what is known as singularity?

>>8873413
Every black hole is a singularity, anon. Smashing black holes together simply combines them and makes for a more massive singularity.

>>8873424
Then I guess the next question would be, what exactly is singularity? People use that word a lot though I never really hear a solid definition of what it entails. Is it simply the state of everything becoming one? If so, what would that mean if we were to become one or whole? What would that mean for the universe if it reached a state of singularity? Was the universe in a state of singularity before the big bang?

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>>8873404
Funny you should say that. Mixing perspectives was the topic of the previous chapter. Here's an excerpt of Chapter 11 of Thorne's book.

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>>8873404
>continued
And here is a bit from Chapter 12, the chapter I didn't read yet on the development of the ideas of Hawking radiation and understanding of a black hole's entropy.
>...the Bardeen— Carter— Hawking laws of black-hole mechanics are the laws of thermodynamics in disguise, and that, as Bekenstein had claimed two years earlier, a black hole has an entropy proportional to its surface area.
>Hawking’s calculations said more. Once the hole’s spin has slowed, its entropy and the area of its horizon are proportional to its mass squared, while its temperature and surface gravity are proportional to its mass divided by its area, which means inversely proportional to its mass. Therefore, as the hole continues to emit radiation, converting mass into outflowing energy, its mass goes down, its entropy and area go down, and its temperature and surface gravity go up. The hole shrinks and becomes hotter. In effect, the hole is evaporating.
>Thorne, Kip (1995-01-17). Black Holes & Time Warps: Einstein's Outrageous Legacy (Commonwealth Fund Book Program) (p. 436). W. W. Norton & Company. Kindle Edition.

>>8872873
But that's exactly what's happening! The mass is so dense that it collapses beyond white dwarf status (max density of matter based on electron degeneracy pressure), further beyond neutron star status (max density of matter based on nucleon repulsion, the density of atomic nuclei), to something beyond, the singularity, something beyond the definition of matter. The mass is still there but it's now mass without matter, a separate phenomenon from the original normal matter-mass union of the collapsing stellar core.

>>8873586
>Mass without matter.
Sounds a lot like dark matter.
>could a black hole be a dark matter generator?
Anyway, whimsical speculation aside.

The questions I ask is:
>when does energy have mass?
Or
>Why doesn't entropy convert mass into energy?

But there is some difference between the two models. Aside from the authors observation, that is. The charged membrane model actually prevents most matter from crossing through the membrane while the empty-but-curved space model allows most matter to free fall into the black hole.

The charged membrane theory would suggest that two black holes would have a devil of a time colliding. While the classical model predicts no such difficulties.

However, the charged membrane theory would prevent a black hole from converting all its mass into energy because it never gains mass from outside the event horizon. Mass would fairly quickly settle into equilibrium between entropy, mass and gravity. Entropy would convert just enough mass to energy to reduce gravity enough to prevent entropy from converting any more mass. The energy produced would quickly dissipate into the surrounding space, but never be released beyond the event horizon except through quantum tunneling.

And yet, the theory doesn't quite sit right with me. Largely because it suggests very little external matter ever passes through the event horizon due to the tremendously repulsive electrical charge.

Am I wrong?

My theory is that the universe expands at different rates in different areas, which pushes timespace like a canoe paddle through water. So instead of the holes themselves being extremely strong gravitationally, it is actually a reaction of the timespace pushing against it.

>If mass is converted into energy, then that mass is no longer bending space

Who said that?

Energy definitely will bend spacetime.

>>8873921
Then please explain how energy has mass or how it can bend space without mass.

>>8873982
>Then please explain how energy has mass

It doesn't "have" mass, it IS mass. Energy and mass are the same thing. It's not a transformation relationship, it's an equivalence relationship, energy IS mass and vice versa.

How else would photons be effected by gravity if they were massless? And since they're effected by gravity, they also source it.