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(Forbes)   Do gravitational waves pass right through black holes? Or do black holes swallow up gravitational waves?   (forbes.com) divider line
    More: Interesting, General relativity, Gravitational waves, black holes, disk of the Sun. Other, event horizon, empty space, dark matter, gravitationalwaves  
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475 clicks; posted to STEM » on 18 Jun 2021 at 8:54 AM (6 weeks ago)   |   Favorite    |   share:  Share on Twitter share via Email Share on Facebook



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View Voting Results: Smartest and Funniest
 
2021-06-18 2:45:29 AM  
Ethan Siegel has finally jumped the shark.
 
2021-06-18 3:50:49 AM  

Spectrum: Ethan Siegel has finally jumped the shark.


Yeah, but that shark had a black hole in it.
 
2021-06-18 7:50:29 AM  

Dr. DJ Duckhunt: Spectrum: Ethan Siegel has finally jumped the shark.

Yeah, but that shark had a black hole in it.


Fark user imageView Full Size
 
2021-06-18 8:38:45 AM  
Why don't you go ask them?
 
2021-06-18 8:40:41 AM  
More importantly, does it convert a 2d world into 3d?
 
2021-06-18 8:51:38 AM  

Merltech: More importantly, does it convert a 2d world into 3d?


When they hit the surface of that black hole, they're going to wish their fathers had never met their mothers.  That's for sure.
 
2021-06-18 9:39:08 AM  
What happens when a wave passes over a drain?

My guess is that a very similar thing happens.  The black hole is a feature of space-time curvature.  So is the gravitational wave.  Seems like you are asking what happens when to features in a medium interact, which doesn't strike me as that novel or interesting.  But maybe some weird shiat happens when you do the math.  Who knows.

Guessing they want to explore this to try and model Hawking Points in the MBR?
 
2021-06-18 9:51:58 AM  

Spectrum: Ethan Siegel has finally jumped the shark.


I don't know about that, but he did use a lot of words to just to say, yes, black holes affect gravity waves the same way they affect they affect all other known massless radiation.
 
2021-06-18 9:55:32 AM  

BeesNuts: What happens when a wave passes over a drain?

My guess is that a very similar thing happens.  The black hole is a feature of space-time curvature.  So is the gravitational wave.  Seems like you are asking what happens when to features in a medium interact, which doesn't strike me as that novel or interesting.  But maybe some weird shiat happens when you do the math.  Who knows.

Guessing they want to explore this to try and model Hawking Points in the MBR?


You have to decide if you think gravity is a fundamental force, or not.  Space-Time is also a construct that we have to decide whether exists, or not.  When we dig down into how things work, if this is not an event-driven universe, these things become symptoms not causes, and flexibility suddenly creeps in.

I personally think quantum is the result of extreme situations where the hidden flexibility of probability that is knitted into the fabric of the universe is revealed.We've spent a lot of time and effort building constructs to explain everything, but I think we're getting ridiculous.  I think we've gone too far, and need to take a big step back from it.It was fun being a part of the DØ and ICECUBE, and I love the ease of the Standard Model.  But as far as what's really going on, I think those are more of a convenience for scientists to discuss processes and experiment plans or results, than they are a good window into what's real.
 
2021-06-18 10:41:14 AM  
I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.
 
2021-06-18 12:12:29 PM  

sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.


Yeah, in the 'keeping it simple,' way of talking about things, if your space-time depression is deep enough to cause a topographical circle with respect to 3x10^8 m/s, I think you're done.
 
2021-06-18 12:26:28 PM  

aungen: BeesNuts: What happens when a wave passes over a drain?

My guess is that a very similar thing happens.  The black hole is a feature of space-time curvature.  So is the gravitational wave.  Seems like you are asking what happens when to features in a medium interact, which doesn't strike me as that novel or interesting.  But maybe some weird shiat happens when you do the math.  Who knows.

Guessing they want to explore this to try and model Hawking Points in the MBR?

You have to decide if you think gravity is a fundamental force, or not.  Space-Time is also a construct that we have to decide whether exists, or not.  When we dig down into how things work, if this is not an event-driven universe, these things become symptoms not causes, and flexibility suddenly creeps in.

I personally think quantum is the result of extreme situations where the hidden flexibility of probability that is knitted into the fabric of the universe is revealed.We've spent a lot of time and effort building constructs to explain everything, but I think we're getting ridiculous.  I think we've gone too far, and need to take a big step back from it.It was fun being a part of the DØ and ICECUBE, and I love the ease of the Standard Model.  But as far as what's really going on, I think those are more of a convenience for scientists to discuss processes and experiment plans or results, than they are a good window into what's real.


While agnosticism about somethings on the bleeding edge of physics is reasonable, I don't think General Relativity is up for grabs.  It predicted Black Holes AND Gravitational Waves.  And there's nothing quantum about working entirely within that framework.

The REALLY crazy shiat is whether that event is somehow encoded without the black hole.  Does it "remember" the event, in a manner of speaking.  At that point, we're *way* deeper in the weeds than asking how two gravitational disturbances interact with one another.

I will readily admit that doing the actual mathematics surrounding such an event probably requires some wacky synthesis of navier-stokes and general relativity or something nuts like that, and I'm not the physistician to try and pull that off.
 
2021-06-18 12:32:13 PM  

sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.


This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.
 
2021-06-18 3:26:13 PM  

BeesNuts: aungen: BeesNuts: What happens when a wave passes over a drain?

My guess is that a very similar thing happens.  The black hole is a feature of space-time curvature.  So is the gravitational wave.  Seems like you are asking what happens when to features in a medium interact, which doesn't strike me as that novel or interesting.  But maybe some weird shiat happens when you do the math.  Who knows.

Guessing they want to explore this to try and model Hawking Points in the MBR?

You have to decide if you think gravity is a fundamental force, or not.  Space-Time is also a construct that we have to decide whether exists, or not.  When we dig down into how things work, if this is not an event-driven universe, these things become symptoms not causes, and flexibility suddenly creeps in.

I personally think quantum is the result of extreme situations where the hidden flexibility of probability that is knitted into the fabric of the universe is revealed.We've spent a lot of time and effort building constructs to explain everything, but I think we're getting ridiculous.  I think we've gone too far, and need to take a big step back from it.It was fun being a part of the DØ and ICECUBE, and I love the ease of the Standard Model.  But as far as what's really going on, I think those are more of a convenience for scientists to discuss processes and experiment plans or results, than they are a good window into what's real.

While agnosticism about somethings on the bleeding edge of physics is reasonable, I don't think General Relativity is up for grabs.  It predicted Black Holes AND Gravitational Waves.  And there's nothing quantum about working entirely within that framework.

The REALLY crazy shiat is whether that event is somehow encoded without the black hole.  Does it "remember" the event, in a manner of speaking.  At that point, we're *way* deeper in the weeds than asking how two gravitational disturbances interact with one another.

I will readily admit that doing the actual ...


Uh ... Of course quantum and general relativity are up for grabs.  The rivalry is literally the highest fruit on the tree.  If you seal that breach, you're the goose and the golden egg, getting the Nobel, and going down in the history books.  In 2020 we had some interesting studies on white dwarf measurements that may have provided the first real link between them.  This is stuff being worked on.

General Relativity is absolutely settled if you're not worried about details.  But if you are, you'd better be careful.  There are holes in it.  Big, black holes.
 
2021-06-18 3:41:26 PM  

BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.


Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.
 
2021-06-18 3:43:18 PM  

hawcian: BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.

Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.


Gravity waves travel at the speed of propagation.  Light slows down as it passes through a medium.
 
2021-06-18 4:10:28 PM  

aungen: hawcian: BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.

Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.

Gravity waves travel at the speed of propagation.  Light slows down as it passes through a medium.


Light doesn't slow down through a medium, the pathway is lengthened by bouncing around inside the medium before it exits at the same constant speed it maintained.

Gravity is an artifact of the spacetime continuum itself, and the 'nothing is faster than light' rules of GenRev only apply to physical objects travelling thru said continuum.  The difference is why cosmic inflation was able to happen.

I think.
 
2021-06-18 4:54:19 PM  

mcmnky: Spectrum: Ethan Siegel has finally jumped the shark.

I don't know about that, but he did use a lot of words to just to say, yes, black holes affect gravity waves the same way they affect they affect all other known massless radiation.


Yeah, that's entirely on brand.

If we assume a spherical shark of uniform density traveling at a relative velocity in the ergosphere of a supermassive galactic black hole, he's always been jumping it.
 
2021-06-18 4:56:56 PM  

AdrienVeidt: aungen: hawcian: BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.

Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.

Gravity waves travel at the speed of propagation.  Light slows down as it passes through a medium.

Light doesn't slow down through a medium, the pathway is lengthened by bouncing around inside the medium before it exits at the same constant speed it maintained.

Gravity is an artifact of the spacetime continuum itself, and the 'nothing is faster than light' rules of GenRev only apply to physical objects travelling thru said continuum.  The difference is why cosmic inflation was able to happen.

I think.


c  is the maximum speed light can travel through spacetime. There's no actual limit on velocity of spacetime itself.
 
2021-06-18 5:20:50 PM  

leeksfromchichis: AdrienVeidt: aungen: hawcian: BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.

Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.

Gravity waves travel at the speed of propagation.  Light slows down as it passes through a medium.

Light doesn't slow down through a medium, the pathway is lengthened by bouncing around inside the medium before it exits at the same constant speed it maintained.

Gravity is an artifact of the spacetime continuum itself, and the 'nothing is faster than light' rules of GenRev only apply to physical objects travelling thru said continuum.  The difference is why cosmic inflation was able to happen.

I think.

c  is the maximum speed light can travel through spacetime. There's no actual limit on velocity of spacetime itself.


Particles that travel faster than light through a medium emit what is called Cherenkov radiation, which can be seen as a blue shockwave of light behind them.  Muons do this, for example. And neutrinos can arrive before the light from a supernova.  Both items are specifically used in large scale multinational experiments.

None of these particles travel faster than propagation speed (c).  Bosons like light travel at propagation speed, and are slowed down by interactions and entanglements.  Particles like neutrinos go slightly slower, but ignore matter.

So you get a neutrino pulse sooner than you get a light pulse from a dying star, almost every time.  A neutrino wave can alert telescopes to turn in a certain direction to look for a boom.
 
2021-06-18 6:25:27 PM  

aungen: leeksfromchichis: AdrienVeidt: aungen: hawcian: BeesNuts: sxacho: [snip for length]

Particles that travel faster than light through a medium emit what is called Cherenkov radiation, which can be seen as a blue shockwave of light behind them.  Muons do this, for example. And neutrinos can arrive before the light from a supernova.  Both items are specifically used in large scale multinational experiments.

None of these particles travel faster than propagation speed (c).  Bosons like light travel at propagation speed, and are slowed down by interactions and entanglements.  Particles like neutrinos go slightly slower, but ignore matter.

So you get a neutrino pulse sooner than you get a light pulse from a dying star, almost every time.  A neutrino wave can alert telescopes to turn in a certain direction to look for a boom.


Sure, light can arrive later than neutrinos or gravity waves, because light interacts with the medium it travels through, but BeesNuts was talking about gravitational waves escaping black holes. The implication is that gravitational waves can travel faster than the propagation speed of light (they even specifically said "propagate faster than light").
 
2021-06-18 10:39:01 PM  
light speed and propagation speed are not always the same thing.
 
2021-06-18 11:10:13 PM  
Gravitational waves, which do not interact the same as light waves, should travel at propagation speed (c), and not slow down like light does.

The ONLY thing I wonder about, is whether a gravity wave can ripple that first topographical circle around a black hole relative to propagation speed.  I think it can.
 
2021-06-18 11:11:41 PM  
And if you're still upset about me saying light slowing down, then read up on general relativity and the event driven universe, which is why I brought those up in the first place.
 
2021-06-19 12:14:10 AM  
So are black holes bigger on the inside, like a tardis?

They're constantly warping space and that curved space ends up inside the event horizon.
 
2021-06-19 9:03:18 AM  

hawcian: BeesNuts: sxacho: I would guess that any gravity waves that would reach the event horizon would be lost to the black hole while any that don't reach the event horizon will be bent in proportion to the distance away.

This presupposes that gravity is affected by gravity.  But I tend to agree that it would distort the wave as it passed through.  However, gravity waves can technically propagate faster than light, so it's *possible* for the entire wave to exit a black hole, with the most extremely affected portion of the gravitational wave getting stretched out by a factor of its velocity relative to the black hole divided by the speed of light.  If it's propagating slower than light speed, I can kind of imagine it locally discombobulating the wave, breaking the causal relationship between two "severed halves" of this cosmic echo.

Under what circumstances can gravity waves travel faster (or slower) than the speed of light? No snark, just genuinely curious.


They are distortions in the fabric of spacetime, so they aren't really "moving", since they are kind of the medium through which they are moving...  More like they are propagating through the medium.  Nothing in special or general relativity gets in the way of that propagation speed exceeding the speed of light.  In fact, the *reason* light can't escape a black hole is because spacetime itself is falling into the hole faster than light speed.

/super simplified, words only explanation.
//Leonard Susskind has a couple excellent lectures on wtf we believe to be happening on the other side of the event horizon that gives excellent background on how cosmologists think about these things.
 
2021-06-19 9:07:34 AM  

SoundOfOneHandWanking: So are black holes bigger on the inside, like a tardis?

They're constantly warping space and that curved space ends up inside the event horizon.


If you really wanna cook your noodle, current theory is that space and time switch dimensional roles the moment you cross the event horizon.  Meaning you can move freely in any direction on the time axis, but that you are inexorably dragged towards the spatial singularity.
 
2021-06-19 9:13:33 AM  

aungen: Gravitational waves, which do not interact the same as light waves, should travel at propagation speed (c), and not slow down like light does.

The ONLY thing I wonder about, is whether a gravity wave can ripple that first topographical circle around a black hole relative to propagation speed.  I think it can.


I'm not so sure...  there's still a question about whether the event horizon is a physical ... thing.  It's external topology might be causally disconnected from the rest of spacetime, and more connected to its internal geometry, whatever the fark that might end up actually being.  The *real* Holographic Principle says that the topology of the event horizon is actually a full informatic description of infalling and radiating matter and energy.  If that's true, then the only way to impact that topology would be to leave something behind in the black hole.

If that's *not* true, then holy hell would that be a life affirming observation to hear about.  It might actually imply that there is no true singularity inside black holes, which would have *huge* implications about deep time.  It'd definitely throw a monkey wrench into Sir Penrose's Conformal Cyclic Cosmology.
 
2021-06-19 1:57:16 PM  
BeesNuts:

I suspect there is no singularity, but someone else will have to figure out how to prove that.  I think you're spot on with the assessment.
 
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