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Surviving in a Black Hole


GlueOn

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I often here how an objects radiation would redshift and then fade when entering a black hole, but this is from an outside perspective. When I hear about the perspective of the object, they say you would “spaghetify” as you approached due to tidal forces of gravity. This is the part that confuses me. 

If space time is stretched, and the object is stretched with it, is it possible that the object would not be able to tell it was rapidly descending through time shells? Wouldn’t the object continue to expierience free fall? From the outside perspective it is accelerating, but from the object’s perspective it is stationary to the things immediately around it. A tape measure next to the object would spaghetti out just like the object, so it would appear to remain a constant length. 

Basically my question boils down to the density of space in, and around a black hole. Is the density of space inside a black hole high enough that what appears to be a singularity from outside, just normal space inside?

 

If i’m Mistaken in something up until now, then ignore this next bit... Space stretches to the point that it pulls time through the EH, so it would never be possible to leave even at faster than light travel; but you could imagine a pocket of universe that thinks it’s walls are expanding away from it on all sides. Ultimately, could our viewable microwave background be an image of an Event Horrizon?

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2 hours ago, GlueOn said:

I often here how an objects radiation would redshift and then fade when entering a black hole, but this is from an outside perspective. When I hear about the perspective of the object, they say you would “spaghetify” as you approached due to tidal forces of gravity. This is the part that confuses me. 

If space time is stretched, and the object is stretched with it, is it possible that the object would not be able to tell it was rapidly descending through time shells? Wouldn’t the object continue to expierience free fall? From the outside perspective it is accelerating, but from the object’s perspective it is stationary to the things immediately around it. A tape measure next to the object would spaghetti out just like the object, so it would appear to remain a constant length. 

Basically my question boils down to the density of space in, and around a black hole. Is the density of space inside a black hole high enough that what appears to be a singularity from outside, just normal space inside?

 

If i’m Mistaken in something up until now, then ignore this next bit... Space stretches to the point that it pulls time through the EH, so it would never be possible to leave even at faster than light travel; but you could imagine a pocket of universe that thinks it’s walls are expanding away from it on all sides. Ultimately, could our viewable microwave background be an image of an Event Horrizon?

Firstly I believe in this day and age, the only defined singularity in a BH, is at the quantum/Planck level where our laws of physics and GR are not applicable. Certainly not due to infinite spacetime curvature and/or density. When we say one would be spaghetified, we are imagining falling in say feet first. The spacetime curvature differential from your head to your toes would be such that spaghetification would happen. Surviving inside a BH is a valid concept, if the BH was large enough and obviously the spacetime curvature less severe, with little tidal gravity affects. A SMBH similar to what exists at the core of most galaxies would be able to be entered without immediate fear of spaghetification.

 

Spacetime

 

Edited by beecee
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But what about the basic idea of relativity; would I spaghettify from my own point of view, or just one on the outside looking in?

If you keep accelerating past the speed of light in “empty” space, do you pancakify? I thought spacetime stretched around you to slow you down from the outside perspective but you wouldn’t just expierience free fall as further acceleration is canceled out by space time stretching. I think you would still feel your acceleration, and the rest of space around you would just appear to move with you a bit. 

If spacetime can stretch to slow us down to an outside view, couldn’t it compress in a BH to appear to speed us up?

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1 hour ago, GlueOn said:

But what about the basic idea of relativity; would I spaghettify from my own point of view, or just one on the outside looking in?

Certainly from your own Frame of reference, and theoretically spaghetification  may even happen this side of the EH, depending on the BH's size and mass.

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If you keep accelerating past the speed of light in “empty” space, do you pancakify? I thought spacetime stretched around you to slow you down from the outside perspective but you wouldn’t just expierience free fall as further acceleration is canceled out by space time stretching. I think you would still feel your acceleration, and the rest of space around you would just appear to move with you a bit. 

From an outside distant FoR, you would never be seen to actually cross the EH...rather just redshifted and slowed until fading from view........Inside and in your own frame, you approach the EH, cross it, and proceed on your one way trip to the singularity

 

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If spacetime can stretch to slow us down to an outside view, couldn’t it compress in a BH to appear to speed us up?

Stretch, I prefer curve or warped, is caused by the mass which exhibits gravity, which "slows" the light to a distant frame. Inside the EH, the warping/curving continues depending on mass, at least up to the quantum/Planck region where our theories then fail us.

I'm not sure how you imagine the BH maybe compressed, but we really can only reason logically about what may happen inside the EH, based on the GR edict that once the Schwarzchild radius of any particular mass is reached an EH forms, and further collapse is compulsory, at least up to the quantum/Planck level where GR itself fails us.

But hey! I'm only a bloody amateur at this game, so lets wait for one of our experts to either agree, or correct any errors or corrections. 

Edited by beecee
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7 hours ago, GlueOn said:

When I hear about the perspective of the object, they say you would “spaghetify” as you approached due to tidal forces of gravity. This is the part that confuses me. 

It is tidal forces. The tides on Earth are effectively a small scale spagghetification of the surface water: https://en.wikipedia.org/wiki/Tidal_force#Explanation

It is caused by the difference in gravitational force (or curvature in GR) between your head and your feet.

7 hours ago, GlueOn said:

Wouldn’t the object continue to expierience free fall?

Yes. 

7 hours ago, GlueOn said:

A tape measure next to the object would spaghetti out just like the object, so it would appear to remain a constant length. 

Not necessarily. It depends what material it was made of. If it was a steel rule, it would probably be stretched less than your relatively soft body. But if it were a paper tape measure, it would perhaps be ripped apart before you.

7 hours ago, GlueOn said:

Basically my question boils down to the density of space in, and around a black hole. Is the density of space inside a black hole high enough that what appears to be a singularity from outside, just normal space inside?

I don't think "density of space" means anything. I suppose you can talk about how the points in the chosen coordinate system move relative to one another. In some, at east, the points would get further apart as you approach the black hole, which could, I suppose, be described as space getting "less dense".

7 hours ago, GlueOn said:

If i’m Mistaken in something up until now, then ignore this next bit... Space stretches to the point that it pulls time through the EH, so it would never be possible to leave even at faster than light travel; but you could imagine a pocket of universe that thinks it’s walls are expanding away from it on all sides.

There are coordinate systems that can be visualised as space "falling into" the black hole.

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Ultimately, could our viewable microwave background be an image of an Event Horrizon?

It is hard to see how. Why would the event horizon produce that radiation? Apart form all the other reasons why the universe is nothing like a black hole....

3 hours ago, GlueOn said:

If you keep accelerating past the speed of light in “empty” space, do you pancakify?

You can't accelerate to the speed of light, and certainly not past it.

But objects moving very fast do "pancakify". For example, the proton-proton collision in the LHC produce results that can only be explained by treating the protons as flattened disks.

3 hours ago, GlueOn said:

If spacetime can stretch to slow us down to an outside view, couldn’t it compress in a BH to appear to speed us up?

Yes, as you fell into the black hole, you would see the universe around you become increasingly blue shifted and sped up. (Until you hit the singularity!)

More here: http://www.edu-observatory.org/physics-faq/Relativity/BlackHoles/fall_in.html

 

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11 hours ago, beecee said:

But hey! I'm only a bloody amateur at this game, so lets wait for one of our experts to either agree, or correct any errors or corrections. 

Right, I’m familiar with the agreed upon theories. Mass causes space time to warp. Black holes are extremely massive so they warp space time A LOT. I am not familiar enough with the math to play with the numbers (I am familiar with modeling with python,) but I wonder if the warping of space time can really break the strong nuclear force or even electromagnetic force and truly cause the way my atoms are connected to change.  Can gravitational forces really tear matter apart? I would think it can warp, but never change matter.

Our best minds can’t definatively prove what’s going on there. I’m wondering if there is some knowledge I’m not aware of that would prove my ideas to be false. Am I wasting my time with these thoughts, or are they possible? 

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23 minutes ago, GlueOn said:

Black holes are extremely massive so they warp space time A LOT.

The important point is that the mass is concentrated in a small volume of space.

23 minutes ago, GlueOn said:

I am not familiar enough with the math to play with the numbers

The basic math you need is probably pretty simple. But this handy on-line calculator will work out a lot of the numbers for you: http://xaonon.dyndns.org/hawking/

That includes surface gravity and tidal forces. It also shows the equations used.

25 minutes ago, GlueOn said:

but I wonder if the warping of space time can really break the strong nuclear force or even electromagnetic force and truly cause the way my atoms are connected to change.  Can gravitational forces really tear matter apart?

I can't imagine why not.

25 minutes ago, GlueOn said:

Our best minds can’t definatively prove what’s going on there.

Science never definitively proves anything. But we have a theory that describes what we think happens around black holes. This still need to be confirmed by direct observation, but all other tests have shown the theory to be correct.

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1 hour ago, GlueOn said:

but I wonder if the warping of space time can really break the strong nuclear force or even electromagnetic force and truly cause the way my atoms are connected to change.  Can gravitational forces really tear matter apart? I would think it can warp, but never change matter.

Gravity as any mass/object approaches the "singularity" will overcome all other forces, including the strong nuclear force, as it is broken down into its most fundamental parts, probably quarks.

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36 minutes ago, beecee said:

Gravity as any mass/object approaches the "singularity" will overcome all other forces, including the strong nuclear force, as it is broken down into its most fundamental parts, probably quarks.

This assumes that general relativity is more fundamental than quantum theory.  The present state of knowledge (as far as I understand)  is that they are incompatible in these extreme circumstances, so no one really knows what happens inside black holes.

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41 minutes ago, beecee said:

Gravity as any mass/object approaches the "singularity" will overcome all other forces, including the strong nuclear force, as it is broken down into its most fundamental parts, probably quarks.

 

2 minutes ago, mathematic said:

This assumes that general relativity is more fundamental than quantum theory.  The present state of knowledge (as far as I understand)  is that they are incompatible in these extreme circumstances, so no one really knows what happens inside black holes.

 

Interesting issue.

 

Has anyone explored the possibility of particles (quantum) tunneling out of a black hole?

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49 minutes ago, mathematic said:

This assumes that general relativity is more fundamental than quantum theory.  The present state of knowledge (as far as I understand)  is that they are incompatible in these extreme circumstances, so no one really knows what happens inside black holes.

While agreeing that quantum theory and GR are incompatible at these levels, and agreeing that we can not be sure what actually happens inside a BH, I'm not convinced that what I said does assume GR as more fundamental then quantum theory. I have also seen and heard discussions of possible quark stars and quark matter: This also dictates that gravity at extreme levels will overcome all other forces. The high pressures that exhibit themselves as gravity increases, are also responsible for EDP and NDP......Obviously the gravity resulting from a BH even overcomes NDP: Cannot we then reasonably assume that even the strong force is overcome near or at the singularity? GR also tells us that once the Schwarzchild radius is reached, further collapse "is compulsory" which afterall is the defining aspect of a BH under GR.

 

I also found this answer at  https://physics.stackexchange.com/questions/30795/what-happens-to-matter-in-extremely-high-gravity?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa

"Extreme gravity essentially equates to extreme pressure. We see a progression in stellar evolution.

The high pressures of the huge gravitational pull of a star is at first counteracted by electromagnetic/thermal interactions between gas particles. However, at a certain point (with enough gravitational pull) these interactions are not enough and the gravitational force overwhelms electromagnetic forces. Positively charged nuclei collide into positively charged nuclei and hydrogen fusion occurs. The star is supported from further collapse via electron degeneracy pressure, where two electrons cannot occupy the same quantum state.

As elements bind into heavier elements, fusion becomes more and more difficult and requires more energy. Eventually the nuclear forces are not sufficient and the star collapses further, allowing carbon to fuse. This carbon fusion is much more energetic than the proceeding fusion and the star explodes. If there is sufficient mass, a supernova occurs and the remnant could be a neutron star (if the star exceeds the Chandrashankar limit of about 1.44 solar masses) or a black hole (if the star exceeds the Tolman-Oppenheimer-Volkoff Limit of 3 solar masses).

In a neutron star, fermi-degeneracy pressure keeps the particles from collapsing down to a gravitational singularity. Essentially there is enough pressure to force electrons into protons and form neutrons (inverse beta decay), and the neutrons are only stopped from colliding with each other by neutron degeneracy pressure. With a large enough mass though, even this is not enough to stop collapse, to either a theoretical quark star or even to a black hole.

So essentially we see as pressure increases, the various forces that keep matter matter-like get overcome. First electromagnetic interactions, then electron degenerecy pressure, then neutron degenercy pressure, and finally a collapse into a singularity/black hole (or something like that).

Edit: In response to the original poster's question, they can theoretically condense further to a quark degenerate matter. The specifics at this level get more fuzzy, since the strong force is difficult to model accurately due to asymptotic freedom. Unless there are particles that make up quarks, this is the lowest level of possible degeneracy".

 

and.... https://physics.stackexchange.com/questions/30795/what-happens-to-matter-in-extremely-high-gravity?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa

and from https://www.quora.com/Why-does-the-general-theory-of-relativity-break-down-at-the-center-of-a-black-hole

extract:

"Although general relativity has no upper limit on how much you can compress matter, theories of quantum gravity might say that it cannot be compressed beyond the Planck Density. It proposes that rather than collapsing into a singularity, the matter within a black hole will collapse until it is about a trillionth of a meter in size. At that point its density would be on the order of the Planck density".

 

 

Edited by beecee
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