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Try To Understand The Center Of A Black Hole


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#18 Flummoxed

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Posted 28 March 2019 - 05:10 PM

Ok but I'm still in favor of the universe being created from the big rip where particles were torn out of expanding space. Is it called the big rip? All I know of cosmology is what little I've interpreted from this forum.

 

The inflationary stage of the universe could have torn apart virtual particles similar to Hawking Radiation, causing them to become real. The nearest experimental proof I can find of this is the Dynamic Casimir Effect which has been proven in 2013 I think. Google will throw something up if your interested.



#19 ralfcis

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Posted 28 March 2019 - 05:24 PM

I don't think it will be hot though, I think it will be the coldest thing possible except for quantum vibrations that cause hawking radiation as Dubble said.  Pauli makes everything harder. Pauli resists compression. Movement makes things softer so there must be minimal movement inside between the resistance Pauli puts up against the compression of gravity. In my example of the event horizon being analogous to c in an away direction, that direction causes the freq of light to be so red-shifted it has 0 freq. 0 freq light would be the ultimate cold light or motionless bosons all overlapping each other on a single wavelength. The event horizon must be analogous to a direction of c that counters c that wants to escape the event horizon.


Edited by ralfcis, 28 March 2019 - 05:26 PM.


#20 Flummoxed

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Posted 28 March 2019 - 05:40 PM

I don't think it will be hot though, I think it will be the coldest thing possible except for quantum vibrations that cause hawking radiation as Dubble said.  Pauli makes everything harder. Pauli resists compression. Movement makes things softer so there must be minimal movement inside between the resistance Pauli puts up against the compression of gravity. In my example of the event horizon being analogous to c in an away direction, that direction causes the freq of light to be so red-shifted it has 0 freq. 0 freq light would be the ultimate cold light or motionless bosons all overlapping each other on a single wavelength. The event horizon must be analogous to a direction of c that counters c that wants to escape the event horizon.

 

Its all relative :) Gravity causes Hawking Radiation like what Hawking said around a BH theoretically. The event horizon of a BH is observable by the heat being given off buy the accretion disc, which is hot plasma, which causes magnetic fields etc. It is not cold due to many collisions in the accretion disc. If you agree with Pauli exclusion principle that would mean no singularity in a BH unless its photons, which can occupy the same point in space. Yep any light trying to leave a BH will be red shifted out of existence unless it curves back in towards the centre relatively speaking. 



#21 ralfcis

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Posted 28 March 2019 - 07:45 PM

The disc  is hot, the hole is cold. Since matter never reaches past the event horizon into the hole, there is no contradiction between the temperature difference. The light trying to leave will be blue shifted to a very high hot frequency (as is observed)  but the light or matter being sucked in will be red shifted to an outside observer and vanish.



#22 VictorMedvil

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Posted 28 March 2019 - 08:05 PM

The disc  is hot, the hole is cold. Since matter never reaches past the event horizon into the hole, there is no contradiction between the temperature difference. The light trying to leave will be blue shifted to a very high hot frequency (as is observed)  but the light or matter being sucked in will be red shifted to an outside observer and vanish.

 The Larger the hole the lower the temperature of the insides of the hole but your right the outside of the black hole is very high temperature if it is consuming mass, but if the black hole is not consuming mass actually the temperature of the outside of the black hole is quite cold aswell. The reason for the redshift upon trying to escape of incoming matter is due to the intense gravity that the points of space are actually closer in one direction than the other due to general relativity. It would be blueshifted in the direction toward the black hole I think and redshifted trying to escape due to the way the fabric of time-space is bent toward the black hole, you reversed them I think. https://secretsofuni...-actually-mean/

 

Grav-z.jpg

 

The Equation for Gravitational Redshift 

 

31-gravitational-redshift.png


Edited by VictorMedvil, 28 March 2019 - 08:15 PM.


#23 ralfcis

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Posted 28 March 2019 - 08:52 PM

Ok.



#24 Flummoxed

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Posted 29 March 2019 - 03:52 AM

The disc  is hot, the hole is cold. Since matter never reaches past the event horizon into the hole, there is no contradiction between the temperature difference. The light trying to leave will be blue shifted to a very high hot frequency (as is observed)  but the light or matter being sucked in will be red shifted to an outside observer and vanish.

 

Depends on where you measure the temperature. A thermos flask appears cold from the outside, but inside it can be very hot. The only thing getting out of a BH if at all will be Black Body Radiation or Hawking Radiation this is due to the intense gravitational field acting like a thermos flask keeping the heat in. The laws of thermodynamics if anything gets squashed it gets hot, this includes crushing by a black holes gravity. Its must be hot inside, for boson stars to be even plausible, or any of the other options given above to be plausible..



#25 ralfcis

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Posted 29 March 2019 - 06:47 AM

The act of crushing gets things hot because you are extracting heat from them by limiting the internal motion which is the same as cooling them. So you get a burst of heat outward. A diamond is created under intense heat and pressure but it doesn't stay hot forever, in fact it's the coolest thing we know. Heat can't be radiated from inside a black hole not because gravity keeps the heat in but because there is no heat, gravity has tamped down all motion within the hole. Again, I say all this without any authority or knowledge.


Edited by ralfcis, 29 March 2019 - 06:48 AM.


#26 ralfcis

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Posted 29 March 2019 - 06:56 AM

I said ok to the red shift/ blue shift discussion earlier and I understand it but don't agree with it. Victor said light is blue shifted going into a black hole because space gets shrunk and time slows as you get nearer the hole. If a burning chunk of matter was sourcing light as it fell in, it would get accelerated to near -c and that should mean its light would be red-shifted. According to relativity, we would observe that object's space contract and time dilate just from velocity effects. Yet that spacetime contraction results in a red shift and gravity's spacetime contraction results in a blue-shift? Please explain what I'm missing here.



#27 A-wal

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Posted 29 March 2019 - 08:15 AM

Time dilation, length contraction and redshift all approach infinity as an object approaches the event horizon from the frames of all more distant observers.

This means that in the frames of all more distant observers the velocity of any objects approaching an event horizon decreases due to the exponential increase of time dilation and length contraction over the same distance reduction as they get closer to the event horizon, even after Doppler shift has been accounted for and even if they accelerate under their own power towards the horizon.

Objects never reach an event horizon in the frames of any more distant observers, they just get more and more time dilated and length contracted as they approach. This isn't in any way contentious or controversial, it's the standard description and widely accepted. Any properties of black holes to do with matter that fell towards them is due to matter outside of the event horizon because it can only ever be outside of the event horizon.

 

Regardless of the lifespan of the black hole, all matter remains external so it's kind of a moot point to think about the interior of black holes when no matter can ever experience it.



#28 ralfcis

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Posted 29 March 2019 - 08:43 AM

"This means that in the frames of all more distant observers the velocity of any objects approaching an event horizon decreases"

 

This is like saying the closer one is observed to moving at the speed of light, the closer he looks to not moving at all. His velocity through time is observed to slow as his observed velocity through space increases to c. 

 

"Objects never reach an event horizon in the frames of any more distant observers,"

 

You're basing that opinion on the belief that if we observe time stand still in a moving frame, then our time also stands still watching it. Nope, the object makes it to the event horizon (I believe converted into energy) from any outside perspective. Hopefully the guys on here will back me up so the discussion will not devolve.

 

"Regardless of the lifespan of the black hole, all matter remains external so it's kind of a moot point to think about the interior of black holes when no matter can ever experience it."

 

A gluon is a boson that can be weighed so is it matter or energy? I'd say any type of inbound boson can make it past the event horizon (how else would a black hole grow) so if you consider a boson matter because it can be weighed on a scale, then "matter" can make it into the interior of black holes.

 

Since science is about trying to understand stuff, I don't think there are any moot points (or infinities that don't tend to a  finite value) that are acceptable.


Edited by ralfcis, 29 March 2019 - 08:59 AM.


#29 A-wal

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Posted 29 March 2019 - 09:19 AM

"This means that in the frames of all more distant observers the velocity of any objects approaching an event horizon decreases"

 

This is like saying the closer one is observed to moving at the speed of light, the closer he looks to not moving at all. His velocity through time is observed to slow as his observed velocity through space increases to c.

Yes, time dilation and length contraction approach infinity in the frame of a more distant observer as the object approaches the event horizon.

 

The event horizon is the point where the falling observer would be accelerated past the speed of light relative to all more distant observers, which is why objects wouldn't be able to escape from inside the horizon (if they were even able to reach it), because no amount of acceleration can ever allow any object to reach the speed of light relative to any other object which is why the time dilation and length contraction of objects approaching an event horizon approaches but never reaches infinity as they approach but never reach the horizon.

 

"Objects never reach an event horizon in the frames of any more distant observers,"

 

You're basing that opinion on the belief that if we observe time stand still in a moving frame, then our time also stands still watching it. Nope, the object makes it to the event horizon (I believe converted into energy) from any outside perspective. Hopefully the guys on here will back me up so the discussion will not devolve.

No I'm basing that opinion on the fact that it's how this works, and this is supported by the standard description of black holes given by physicists.

 

Of course time in the distant frame is moving normally, but the falling object is becoming more and more length contracted and time dilated as they approach the horizon. If they were to reach the horizon they'd be frozen there, but that would require infinite time dilation and length contraction and an infinite amount of proper time in the frame of the distant observer. If you want to focus on time dilation, their watch continually slows as they approach the event horizon but never stops.

 

They shouldn't back you up and if they do it will be their own black hole model, not the standard one.

 

"Regardless of the lifespan of the black hole, all matter remains external so it's kind of a moot point to think about the interior of black holes when no matter can ever experience it."

 

A gluon is a boson that can be weighed so is it matter or energy? I'd say any type of inbound boson can make it past the event horizon (how else would a black hole grow) so if you consider a boson matter because it can be weighed on a scale, then "matter" can make it into the interior of black holes.

 

Since science is about trying to understand stuff, I don't think there are any moot points (or infinities that don't tend to a  finite value) that are acceptable.

It doesn't make any difference if it's a gluon, another type of boson or anything else. Time dilation and length contraction don;t distinguish between them.

 

There are conceptual infinities but no practical ones. Time dilation, length contraction, Doppler shift and time it takes for a falling object to reach a black hole all approach infinity as the event horizon is approached by the falling object.



#30 ralfcis

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Posted 29 March 2019 - 02:12 PM

Forget the black hole for a minute. So according to relativity,  a photon, from its perspective, is absorbed instantaneously as its emitted even if the distance it may travel could be the length of the universe. Outside the photon, we would age 14 billion yrs in its instantaneous trip. It sees the outside space contracted to nothing and if it had the chance to see our time outside itself, it would see it stopped because that's what reciprocal time dilation means.

 

Except it doesn't mean that. Just because light may recede from us at c doesn't mean our relative velocity to the light is also c. MMX proved we can't have a relative velocity to light. Time doesn't stop from the photon's perspective because we can see its frequency which is a function of time. If time stopped, we'd see light red-shifted to a flat line. The only time that happens is when a material source of light is going near c. 

 

Now your argument is a boson which travels at c never reaches the event horizon but it can easily reach the end of the universe instantaneously? It can do that in 14 billion of our yrs but it takes infinite of our time to fall into the event horizon? Whether normal matter hits the event horizon is a moot point. No matter can cross the event horizon because no matter can travel at c. So if the matter isn't directly adding to the bulk of the black hole, where is all that matter going. Well we see a lot of energy being release from the accretion disc. Could all that matter going in be equal to most of the energy going out (except for the energy that makes it into the hole as bosons)?



#31 Moronium

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Posted 29 March 2019 - 02:46 PM

Yes, time dilation and length contraction approach infinity in the frame of a more distant observer as the object approaches the event horizon.

 

 

With abject solipsism as his ontology, Awol will never stop confusing himself.

 

According to SR (which is false, but let's leave that aside for a moment) the assertion quoted above is false.  The time dilation is not "in the frame of a more distant observer."  It is only in the distant frame of the other object itself, as the distant observer falsely deduces what is happening in that frame to be, no more.

 

Time in the frame of the distant observer is totally unaffected.

 

How about in the frame of the object approaching a black hole?  In that frame, the object is at complete and absolute rest, and is not moving at all.  But the black hole is approaching him.  Time does not "stop" for him at all.

 

According to Awol, though, the mere perceptions of a distant observer FORCES time to virtually stop in the object near the black hole.

 

It's all utter absurdity, and Awol actually thinks it "proven fact."  That tells you just how much he knows about proof, and fact.


Edited by Moronium, 29 March 2019 - 02:50 PM.


#32 GAHD

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Posted 29 March 2019 - 02:53 PM


The event horizon is the point where the falling observer would be accelerated past the speed of light relative to all more distant observers, which is why objects wouldn't be able to escape from inside the horizon (if they were even able to reach it), because no amount of acceleration can ever allow any object to reach the speed of light relative to any other object which is why the time dilation and length contraction of objects approaching an event horizon approaches but never reaches infinity as they approach but never reach the horizon.

...AFAICT it's more that space itself would be "pinched off" from bending of gravity. Light can't escape not because of speed, but because past the horizon ALL paths lead back to the singularity; there IS no way "out" as that direction no longer exists.



#33 A-wal

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Posted 29 March 2019 - 02:55 PM

Forget the black hole for a minute. So according to relativity,  a photon, from its perspective, is absorbed instantaneously as its emitted even if the distance it may travel could be the length of the universe. Outside the photon, we would age 14 billion yrs in its instantaneous trip. It sees the outside space contracted to nothing and if it had the chance to see our time outside itself, it would see it stopped because that's what reciprocal time dilation means.

I suppose so. The frame of a photon doesn't really make sense, the only valid frames are ones in which time perceiving matter move at velocities lower than c relative to each other and energy moves at c relative to all of them (if they're inertial).

 

So if the matter isn't directly adding to the bulk of the black hole, where is all that matter going. Well we see a lot of energy being release from the accretion disc. Could all that matter going in be equal to most of the energy going out (except for the energy that makes it into the hole as bosons)?

Some of it is released through jets. If the black hole looks like it's taking in matter and increasing it's mass it's because of matter falling towards the horizon so there's more mass in the area of space where the black hole is, not because the black hole is actually growing.

 

Just to be clear, it is a fact that in the mainstream model of black holes nothing can ever reach an event horizon from the frame of a more distant observer.



#34 A-wal

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Posted 29 March 2019 - 03:04 PM

...AFAICT it's more that space itself would be "pinched off" from bending of gravity. Light can't escape not because of speed, but because past the horizon ALL paths lead back to the singularity; there IS no way "out" as that direction no longer exists.

That is another way of looking at it, that a direction that leads out of the black hole no longer exists. Also that time and space switch over so that the point in space that was from an external perspective where the singularity was situated is now a point in the inescapable future of an observer inside the horizon.

 

It is also perfectly valid to view it simply as objects being accelerated beyond a velocity of c relative to all external observers, and therefore no amount of acceleration is enough to cross back.

 

These are all descriptions of something that can never actually happen though. All objects remain outside the event horizon from the frames of all external observers, regardless of how close any external observer gets.


Edited by A-wal, 29 March 2019 - 03:06 PM.