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Try To Understand The Center Of A Black Hole


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#35 Dubbelosix

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Posted 29 March 2019 - 03:06 PM

It is often said, a photon has no frame of reference, because it has no passage of time.

 

This sounds very cryptic... true, but cryptic. I tend to say instead, a frame of reference is something with inertial mass. This generalizes it a bit better. This statement is true of all kinds of matter, acting as clocks - just as it is true, that the lack of a reference frame does not just apply to photons, but all kinds of energy too.



#36 Moronium

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Posted 29 March 2019 - 03:09 PM

If a distant observer blindfolded himself, he would see nothing.  So what?  It would make no difference either way. Nothing the distant observer thinks he "sees" can affect the distant object itself.



#37 A-wal

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Posted 29 March 2019 - 03:12 PM

If a distant observer blindfolded himself, he would see nothing.  So what?  It would make no difference either way. Nothing the distant observer thinks he "sees" can affect the distant object itself.

:) The subject matter is clearly way over your head. Don;t stop though, it's quite funny.



#38 Moronium

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Posted 29 March 2019 - 03:16 PM

:) The subject matter is clearly way over your head. Don;t stop though, it's quite funny.

 

What is the "subject matter" here?  Seeing who can draw the most ridiculous conclusions and contradict both logic and objective reality the most and most often, that it?

 

You're right, its not a subject matter that I am well-versed in. 


Edited by Moronium, 29 March 2019 - 03:20 PM.


#39 GAHD

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Posted 29 March 2019 - 03:20 PM

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.

Except...no.
For one, there's no observations of that.
For two, we're still trying to understand the superluminal motion of cosmic jets(which would be enough to escape a black hole up to ~1/3 Schwarzschild if it is actually superluminal, as observed, at the angles observed). Those jets are fairly often attributed to SMBH and are what's causing a quasar/BH nomenclature debate.
 



#40 A-wal

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Posted 29 March 2019 - 03:35 PM

Except...no.
For one, there's no observations of that.

Well there couldn't be. What a distant observer would observe is acceleration that approaches infinity as the a falling object approaches the event horizon. I should be careful saying the falling object is approaching the speed of light though because they're actually slowing down relative to a distant observer as they approach the horizon.

 

They're in a region where time dilation and length contraction are approaching infinity and if you take that into account their velocity relative to all external observers approaches the speed of light as they approach the event horizon. Their velocity relative to different observers varies depending on the distance of the observer but it's always approaching the speed of light at the horizon.

 

For two, we're still trying to understand the superluminal motion of cosmic jets(which would be enough to escape a black hole up to ~1/3 Schwarzschild if it is actually superluminal, as observed, at the angles observed). Those jets are fairly often attributed to SMBH and are what's causing a quasar/BH nomenclature debate.

Superluminal, no. I'd bet anything on that. Matter with more mass than Jupiter is being accelerated to over 99% c so they're pretty powerful electromagnetic jets but nothing is going faster than the speed of light for all sorts of reasons. It would be going backwards in time for one thing.



#41 Moronium

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Posted 29 March 2019 - 03:36 PM

Awol, you are selectively applying the "knowledge" about SR which you presume to have.  I understand that, because it can't be consistently applied.

 

Among many other mistakes, you have violated a basic tenet of SR, which absolutely prohibits the use of a preferred frame.

 

You're taking the frame of a distant observer and treating it as preferred.  Its, and only its, frame of reference is "true."  The frame of the distant object can only be false.  It must conform its motion to what your preferred frame says it must be, the way you would have it.


Edited by Moronium, 29 March 2019 - 03:41 PM.


#42 GAHD

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Posted 29 March 2019 - 03:44 PM

Well there couldn't be. What a distant observer would observe is acceleration that approaches infinity as the a falling object approaches the event horizon. I should be careful saying the falling object is approaching the speed of light though because they're actually slowing down relative to a distant observer as they approach the horizon.

 

They're in a region where time dilation and length contraction are approaching infinity and if you take that into account their velocity relative to all external observers approaches the speed of light as they approach the event horizon. Their velocity relative to different observers varies depending on the distance of the observer but it's always approaching the speed of light at the horizon.

 

Superluminal, no. I'd bet anything on that. Matter with more mass than Jupiter is being accelerated to over 99% c so they're pretty powerful electromagnetic jets but nothing is going faster than the speed of light for all sorts of reasons. It would be going backwards in time for one thing.



Except, we HAVE seen it. Go search for the raw papers. A lot of the math for it works out to .999...9C at low angles of incident, but we've observed them at large angles too. Which is screwy, there's a few other models that let it happen if somehow the space itself is being contracted along one plane and we're viewing the emissions from another angle. We do NOT fully understand it yet though. The observable universe is a lot stranger than you can imagine. :excl2:



#43 A-wal

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Posted 29 March 2019 - 03:45 PM

You're taking the frame of a distant observer and treating it as preferred.

I'm doing no such thing. This isn't inertial by the way, the falling object is accelerating so time dilation and length contraction are nit reciprocal in this case, so don't even think about going there.

 

And no silly, I'm not claiming that it's the observations of a distant observer that directly affects the frame of the falling observer, I'm simply saying that nothing can reach an event horizon from the from the frame of any distant observer in any finite amount of time. Again this is fully supported by the standard mainstream model for black holes.



#44 A-wal

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Posted 29 March 2019 - 03:47 PM

Except, we HAVE seen it. Go search for the raw papers. A lot of the math for it works out to .999...9C at low angles of incident, but we've observed them at large angles too. Which is screwy, there's a few other models that let it happen if somehow the space itself is being contracted along one plane and we're viewing the emissions from another angle. We do NOT fully understand it yet though. The observable universe is a lot stranger than you can imagine. :excl2:

This is going to be just like those neutrinos that were 'moving faster than c', then 'oh wait, no they're not'. No siht they're not.


Edited by A-wal, 29 March 2019 - 03:48 PM.


#45 VictorMedvil

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Posted 29 March 2019 - 03:48 PM

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.

 

Redshift is loss of energy and Blueshift is gain in energy the object gains energy as it gets sucked into a Black hole due to gravitational potential energy being converted into kinetic, thus the kinetic energy or momentum increases as the points of space are closer together it seems to have a higher frequency the photon, all apart of general relativity.


Edited by VictorMedvil, 29 March 2019 - 03:50 PM.


#46 Dubbelosix

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Posted 29 March 2019 - 03:51 PM

I'm doing no such thing. This isn't inertial by the way, the falling object is accelerating so time dilation and length contraction are nit reciprocal in this case, so don't even think about going there.

 

And no silly, I'm not claiming that it's the observations of a distant observer that directly affects the frame of the falling observer, I'm simply saying that nothing can reach an event horizon from the from the frame of any distant observer in any finite amount of time. Again this is fully supported by the standard mainstream model for black holes.

 

Accepted is too strong perhaps, yes it is true that current model supports an idea that light appears to take forever to pass a horizon, but if this was truly the case, it would present a paradox, because the observer passing the horizon, surely passes it.

 

I have seen better models, such as light being capable of escaping black holes, such as a gravitational aether. The idea is that light can only approach zero speed, but never reach it. There are many problems with thinking ''light just'' freezes in space like this. There are many reasons to avoid these models.



#47 Moronium

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Posted 29 March 2019 - 03:53 PM

This isn't inertial by the way, the falling object is accelerating so time dilation and length contraction are nit reciprocal in this case, so don't even think about going there.

 

1. Inertial or not, SR says that acceleration has no effect on time dilation, so why bring that up?

 

2.  But, you're right about this much:  When an accelerating frame is involved, the speed of light is no longer constant, and can exceed c. Therefore the limitations which SR tries to impose on inertial frames don't even apply.

 

The distant object will enter the black hole.  If is has to exceed c to do that, so what?  Nothing prohibits it.


Edited by Moronium, 29 March 2019 - 03:54 PM.


#48 VictorMedvil

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Posted 29 March 2019 - 03:55 PM

Accepted is too strong perhaps, yes it is true that current model supports an idea that light appears to take forever to pass a horizon, but if this was truly the case, it would present a paradox, because the observer passing the horizon, surely passes it.

 

I have seen better models, such as light being capable of escaping black holes, such as a gravitational aether. The idea is that light can only approach zero speed, but never reach it. There are many problems with thinking ''light just'' freezes in space like this. There are many reasons to avoid these models.

 

Well, there is the photon sphere beyond the event horizon and right above it where photons infinitely loop in circles inside the Blackhole they just get frozen in the direction toward the Black Hole in the R axis. its not that the photons cannot move just not away from the black hole, the photons could twist and turn around the black hole at a radius all they wanted.


Edited by VictorMedvil, 29 March 2019 - 04:00 PM.


#49 Moronium

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Posted 29 March 2019 - 04:01 PM

 I'm not claiming that it's the observations of a distant observer that directly affects the frame of the falling observer, I'm simply saying that nothing can reach an event horizon from the from the frame of any distant observer in any finite amount of time. 

 

If you're not claiming that the observations of a distant observer can affect the distant object, then why is it in the least bit relevant?


Edited by Moronium, 29 March 2019 - 04:09 PM.


#50 GAHD

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Posted 29 March 2019 - 04:13 PM

This is going to be just like those neutrinos that were 'moving faster than c', then 'oh wait, no they're not'. No siht they're not.

More likely the SL jets are localized recreation of inflationary spacetime via some metric we don't understand, or some other distortion via a mechanism we don't understand. Same time, it's observed weirdness; a duplication event like that is not, and doesn't fit the math that I know. Same as with say, Bell's theorem poking holes in rational views on polarization: maybe reality IS stranger than math that way too but I can't rationalize making that leap without observation.



#51 A-wal

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Posted 29 March 2019 - 04:14 PM

Accepted is too strong perhaps, yes it is true that current model supports an idea that light appears to take forever to pass a horizon, but if this was truly the case, it would present a paradox, because the observer passing the horizon, surely passes it.

No it's definitely accepted. It's explicitly shown by the Schwarzschild coordinates, the most widely used coordinate system for describing black holes.

 

And yes, objects aren't slowed from their own perspective and there is a time on their watch when they would reach the event horizon and no, there's no paradox. However long the black hole lasts for, the falling observer won't reach the horizon before the black hole is gone, they will find themselves in the future at the moment the black hole died. No aether required.

 

1. Inertial or not, SR says that acceleration has no effect on time dilation, so why bring that up?

Just making the point that the non-reciprocal time dilation caused by gravitational acceleration has nothing to do with the inertial frames of SR.

 

2.  But, you're right about this much:  When an accelerating frame is involved, the speed of light is no longer constant, and can exceed c. Therefore the limitations which SR tries to impose on inertial frames don't even apply.

 

The distant object will enter the black hole.  If is has to exceed c to do that, so what?  Nothing prohibits it.

Not true, the speed of light never exceeds c, it's slower than c for accelerating observers.

 

If you're not claiming that the observations of a distant observer can affect the distant object, then why is it in the least bit relevant?

Because it shows that over the whole lifespan of black hole, nothing ever reaches its event horizon.

 

Well, there is the photon sphere beyond the event horizon and right above it where photons infinitely loop in circles inside the Blackhole they just get frozen in the direction toward the Black Hole in the R axis. its not that the photons cannot move just not away from the black hole, the photons could twist and turn around the black hole at a radius all they wanted.

They never actually reach the event horizon due to time dilation and length contraction approaching infinity at the horizon. They just get continually slowed as they approach but never reach the point of being frozen at the horizon. Again, all standard stuff as described by Schwarzschild coordinates.


Edited by A-wal, 29 March 2019 - 04:25 PM.