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Try To Understand The Center Of A Black Hole


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Yet another dubious assumption of Awol is that a distant observer would have to perceive an object approaching a black hole as travelling at the speed of light (in the observer's frame, that is).  This assumption does not seem to comport with empirical observation, however.

 

Matter is Going Into this Black Hole at 30% the Speed of Light

SEPTEMBER 25, 2018

 

A team of researchers in the UK have observed matter falling into a black hole at 30% the speed of light. This is much faster than anything previously observed....They used XMM-Newton to examine x-ray spectra from PG211+143.

 

“We were able to follow an Earth-sized clump of matter for about a day, as it was pulled towards the black hole, accelerating to a third of the velocity of light before being swallowed up by the hole.” – Professor Ken Pounds, University of Leicester, Dept. of Physics and Astronomy.

 

The study supports theoretical work already done.

 

 

https://www.universetoday.com/140066/matter-is-going-into-this-black-hole-at-30-the-speed-of-light/

Edited by Moronium
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Well, Black holes are governed by GR and not SR I would take the GR calculations over the SR ones for the Black hole itself everytime which is that gravity does pull the object in after the photon due to SR freezes in place you gotta remember that gravity is curvature and that being frozen solid does not suspend you falling down the sheet of time-space. Though, that the photon cannot move does not effect the space around the object just the object itself,Only objects with energy-mass are subject to SR while the surrounding space may have Gravitational potential energy it does follow the rules of GR and not SR being that GR explains the coordinates of time-space and that SR explains the objects in motion, Curvature can still bend motionless photons, Photons are bent everyday by pass through mirrors which the bending does not necessarily require the photon to move.

 

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Edited by VictorMedvil
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Victor, they also say acceleration has nothing to do with SR and yet we can calculate the age difference in SR using the rindler metric. And in GR, gravity and static acceleration are equivalent so you probably could replace the rindler metric with the riemann tensor and still come up with an answer in SR for a black hole. I'm just spitballin because I just don't know GR at all but I figure if you can break the rules in SR and come up with an answer for age difference due to velocity acceleration, you could probably do the same using gravity acceleration.

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Victor, they also say acceleration has nothing to do with SR and yet we can calculate the age difference in SR using the rindler metric. And in GR, gravity and static acceleration are equivalent so you probably could replace the rindler metric with the riemann tensor and still come up with an answer in SR for a black hole. I'm just spitballin because I just don't know GR at all but I figure if you can break the rules in SR and come up with an answer for age difference due to velocity acceleration, you could probably do the same using gravity acceleration.

 

Well you gotta understand that is doesn't break SR just SR does not have any effect on the gravitational effects on matter, GR is the governing principal of this Time-space still has its hold on objects that are not in motion even objects in stasis by SR will still be drawn in by time-space.

 

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Needless to say the Time-space itself is curved so basically time and space is curved into the Black Hole. The object can be in whatever velocity state it wants to be under SR it still will follow the World Line which is curved.

 

f75399fbe0d4c32ab43a3a56185542f5.jpg

 

In General Relativity there is a Constant curvature of Time and Space when in the presence of Energy of 8πG/C4

 

 

1200px-Stress-Energy-Tensor-contravarian

Tuv  or Tab  basically just states that Energy Density in all forms causes the curvature or "Gravity" in the form of Momentum, Energy, Stress, and Pressure. Even Electromagnetic fields and other fields cause Gravity.

 

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Edited by VictorMedvil
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Right, Vic.  As I understand it, the flat spacetime of SR is simply incompatible with curved spacetime.  SR just doesn't apply.  As I said earlier:

 

the speed of light is not constant in GR, and, in that framework, all bets are off when they are made in reliance on SR.

 

Edited by Moronium
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Moronium, it's a proven scientific fact they are more likely to miss the guy with the checkered flag than to  measure the speed of a chunk of matter as it hits the event horizon as only .3c. But you go ahead and interpret your wiki article literally if you want. I'm just giving you other literal facts to consider.

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According to this source:

 

Relative Speed of Light
Einstein's theory of General Relativity

 

Suppose that you have a clock and a ruler (which is not rotating with respect to stars) and that you are not accelerating (inertial). Locally (where you are) you will always measure the speed of light at 299792.458 km/sec. However in the presence of gravity if I am at a different location than yours then I could measure the speed of light at your location to be any value smaller than or greater than 299792.458 km/sec. It depends on where I am and where you are (it depends on locations). So in the presence of gravity the speed of light becomes relative (variable depending on the reference frame of the observer).

 

 

http://www.speed-light.info/speed_of_light_gravity.htm

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Moronium, it's a proven scientific fact they are more likely to miss the guy with the checkered flag than to  measure the speed of a chunk of matter as it hits the event horizon as only .3c.

 

Well, Ralf, I think the main "scientific fact" that's been established here is that Awol is full of crap, eh?

 

Personally, I've had first hand experience with black holes.  I've been in lots of them.  FWIW, they are extremely difficult to come out of, but it's possible.

Edited by Moronium
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Ok guys enough gum flapping, we have all the ingredients to formulate a numerical example that if no one here can answer, it can at least be posed on the physics stack exchange which I think will return with every possible number under the sun (proving Awal's and Dubble's contention that 9 out of 10 physicists can agree on anything is false). 

 

Together, Alice and Bob are orbiting a black hole at a 3 light month distance. They don't feel any acceleration effects because they're in orbital free fall. They have no relative velocity either to each other or to the black hole. A guy out in space, free from any gravitational effects is watching them orbit the black hole parallel to him so they have no relative velocity to him either, their orbit just looks like the circular bottom of a cone to him. They are also orbiting at a far enough distance from the black hole that there is negligible difference between his and their gravitational field causing GR age difference. So they're all ageing at the same rate.

 

Alice decides to take off from Bob directly towards the black hole at .6c relative to Bob. She will have to spiral in so that she doesn't deviate from a straight line between Bob and the black hole. She has the math skills to determine what a straight line is even in curved space. Now although she starts at a constant relative velocity, her trip through curved space will cause acceleration due to the black hole and in SR, acceleration means age difference between her and Bob. So, easy peasy lemon squeezy, anyone would be able to calculate her total age difference from Bob at the moment she hits the event horizon.

 

After she hits the event horizon, there will be further age difference accruing for a time between them. How long will that time be, what rate will that age difference be accruing, and how much will the total age difference be between Bob and Alice at the end of the accrual period. No guesses, just show me the math please.

 

So go ahead, someone post this question on the physics stack exchange. But remember, if they can't answer it, you will probably be banned for life from ever asking another question. I don't want to take that chance. Anyone brave enough to take this challenge or is more gum flapping the way to go?

 

PS. Or just ask AWal's question: Does an object falling into a black hole ever reach the event horizon before the black hole evaporates?

Edited by ralfcis
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