# Does a black hole really compress things down to a singularity?

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#### acecharly

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##### Does a black hole really compress things down to a singularity?
« on: 23/03/2016 15:45:32 »
Is the event horizon of a black hole not just the point at which matter cannot be crushed down any further? and that after that point something has to give and so instead of it getting more compact it moves either slightly ahead/behind of time relative to the outside of the event horizon so that it is there in the galaxy but that it could for example be 1 second ahead of the galaxies timeframe and continually be behind or ahead of it? but still at the same time allowing gravity to radiate like a left over wave from it being slightly ahead/behind.

* It would give a reason why you could not see the black hole.
* It could give the cause for galaxy rotation being the same on the outside as the inside.
* It could be why particles come into and out of existence as they move back into the galaxies timeframe for a moment.
* It would be a good candidate for dark matter maybe?
* A similar process could be responsible for the inflation period after the big bang?

I know this is looking like a theory but its more questioning really of where I may be going off the beaten track but it would be interesting to see what you guys think.

Cheers

#### evan_au

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #1 on: 23/03/2016 20:03:18 »
Quote from: acecharly
Is the event horizon of a black hole not just the point at which matter cannot be crushed down any further?
No.

For a galactic-mass black hole (mass millions of times greater than the Sun), the tidal forces at the event horizon are not too severe - certainly survivable by a human. But if you blinked you would miss it, since you would be travelling at more than 10% of the speed of light when you crossed it!

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and that after that point something has to give
If you attempt to extrapolate light cones inside an event horizon, they certainly look odd...

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and so instead of it getting more compact it moves either slightly ahead/behind of time relative to the outside of the event horizon so that it is there in the galaxy but that it could for example be 1 second ahead of the galaxies timeframe and continually be behind or ahead of it?
If it were behind our time by 1 second, you would already see it before the object crossed the event horizon. But then would you see 2 of them, and 3...? I don't think this can occur, as it involves creating mass out of nothing!

If it was ahead in time by 1 second, you would just need to wait 1 second, and then you would see it, so it's not hidden by the event horizon.

What happens inside an event horizon is a mystery. But for normal black holes, the fact that the escape velocity exceeds c means that almost nothing comes out, ie we don't know what goes on inside.

#### acecharly

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #2 on: 24/03/2016 17:05:11 »
Quoteand so instead of it getting more compact it moves either slightly ahead/behind of time relative to the outside of the event horizon so that it is there in the galaxy but that it could for example be 1 second ahead of the galaxies timeframe and continually be behind or ahead of it?If it were behind our time by 1 second, you would already see it before the object crossed the event horizon. But then would you see 2 of them, and 3...? I don't think this can occur, as it involves creating mass out of nothing!If it was ahead in time by 1 second, you would just need to wait 1 second, and then you would see it, so it's not hidden by the event horizon.What happens inside an event horizon is a mystery. But for normal black holes, the fact that the escape velocity exceeds c means that almost nothing comes out, ie we don't know what goes on inside.

The reference to a second was just an example it could literally be any time just after that which is perceived within the galaxy. You say that after one second we would then see it as we had caught up with it, but what im trying to say here is that by that point the matter which could not be compressed anymore will be a second further on in time continuously so as we would never catch up with it. Sharing the same point in space but at a different time.

#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #3 on: 24/03/2016 19:26:57 »
There is a point just outside the event horizon where things change. Instead of escape velocity being higher than orbital speed it swaps around so that escape becomes 'easier' than maintaining an orbit. However at this point the orbital speed has to equal the speed of light. This is for a non-rotating Schwarzschild black hole. For a rotating Kerr black hole you then need to include frame dragging. Solid objects will not remain intact very close to a black hole so that this disintegration of solids ensures collapse to a very dense object. How dense? No one knows.
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#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #4 on: 24/03/2016 19:30:01 »
There may be something very wrong with our view of super massive black holes. I am currently attempting to model the energies at the event horizon of various sized black holes and some things just don't add up.
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#### evan_au

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #5 on: 25/03/2016 00:54:58 »
Quote from: JeffreyH
I am currently attempting to model the energies at the event horizon of various sized black holes and some things just don't add up.
You are not the only one. Current gravitational field theories are not "renormalizable", so you get stuck with lots of stubborn infinities near an event horizon, that just won't go away.

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escape becomes 'easier' than maintaining an orbit. However at this point the orbital speed has to equal the speed of light
Could you have the sign wrong?
Just inside the event horizon, you can't escape, even if you could travel at light speed. All light cones point towards the hypothetical singularity of infinite density.

However, just outside the event horizon, processes in an accretion disk use the energy of matter falling into the event horizon to power jets of matter ejected in the direction of the poles, at relativistic speeds. This is the mechanism believed to power quasars.

#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #6 on: 25/03/2016 01:31:09 »
Quote from: JeffreyH
I am currently attempting to model the energies at the event horizon of various sized black holes and some things just don't add up.
You are not the only one. Current gravitational field theories are not "renormalizable", so you get stuck with lots of stubborn infinities near an event horizon, that just won't go away.

Quote
escape becomes 'easier' than maintaining an orbit. However at this point the orbital speed has to equal the speed of light
Could you have the sign wrong?
Just inside the event horizon, you can't escape, even if you could travel at light speed. All light cones point towards the hypothetical singularity of infinite density.

However, just outside the event horizon, processes in an accretion disk use the energy of matter falling into the event horizon to power jets of matter ejected in the direction of the poles, at relativistic speeds. This is the mechanism believed to power quasars.

I have a textbook on differential forms and relativity that also show a light-like orbit at 3m. So no I don't believe my conclusions are wrong. It seems counter intuitive like a lot of relativity.
Fixation on the Einstein papers is a good definition of OCD.

#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #7 on: 25/03/2016 01:34:25 »
Ah don't get me wrong. Escape velocity is still equal to c at the event horizon.
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#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #8 on: 25/03/2016 02:27:38 »
Explanation of the photon sphere.

« Last Edit: 25/03/2016 02:42:04 by jeffreyH »
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#### JoeBrown

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #9 on: 25/03/2016 05:19:01 »
Here's a curious bit of reasoning that explains why blackhole cannot to be a singularity:

Conceptually a singularity is the smallest point possible.  The LIGO observation's data suggest to me that they can't be like that.

I hypothesize that two singularities orbiting one another would find it nearly impossible to ever meet.

Differing masses might logically help resolve or reduce impossibility.

But!  I further hypothesize the frequency distribution detected by LIGO would look a little different if the two resolved into itty bitty singularities.

NO! it seems more likely that the merger is more comparable to the event horizons merging, but I  think reality of the situation is deeper in the cone.  I think the signature would look different otherwise.  BuThat is my opinion.

I'd like to elaborate further, but need to seek answers to questions I've recently started formulating and don't quite know how to pose.  I am working on a beauty of a hypothesis tho.  Hope I can share it soon.
« Last Edit: 25/03/2016 08:18:05 by JoeBrown »
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#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #10 on: 25/03/2016 12:57:58 »
A little clarification on the above.

Escape velocity at the event horizon is given by

$$v\,=\,\sqrt{\frac{2Gm}{r}}$$

Since the light like orbit is at 3Gm the orbital velocity must be higher than the escape velocity since this region is outside the horizon.
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#### jeffreyH

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##### Re: Does a black hole really compress things down to a singularity?
« Reply #11 on: 25/03/2016 13:11:44 »
Further we can think of a basic relationship of dm/dr where r takes on the value of rs for a given value of m. This simplification is non-relativistic and care should be taken when analysing any results.
Fixation on the Einstein papers is a good definition of OCD.