Talk:Black hole/Archive 2

1713:

each other with a frequency of 1hz, you know, goodbye, see you on the other side, etc etc. The guy falling in and looking out sees his pal seeming to wave at him faster and faster. At the same time, the guy watching his partner fall in sees his partner seeming to wave more and more slowly. Now eventually the guy falling in would see his friend on the outside either running out of air and choking or leaving, and then, a short while later (in his refernce frame) he sees tourists from the "future" coming to watch the guy who fell into a black hole, and sees all the kids with their wide-open eyes going "oooo" but everything would seem to be going very fast. To the tourists, who are coming to visit hundreds/thousands of years later (or longer) the guy seems to have come to a virtual standstill in mid-handwave (he has also become very very dim but we'll ignore that for simplicity). As the ill-fated astronaut falls towards the black hole, he sees the entire "future" of the universe flash before his eyes, because it is taking him a literal eternity (from the outside's frame of refernce) to fall in. But to his frame of refence, time doesn't seem to slow (quite obviously), it's just that things on the "outside" speed up, such that the time for him to reach the black hole is an eternity elsewhere in the universe.

1909:, meaning coming up with an accurate model of what's going on with all the observed phenomena. I think we ought to have figured it out by now, but we haven't. So could it be that at some point in the past (say in the 1920's or the 1960's) the scientific community took a wrong turn, and since then they've been piling incorrect theory on top of incorrect theory, packed with fudge factors + special cases and exceptions and shaky math in order to try to make sense of things? The scientific method is supposed to be always encouraging testing, examining everything, including long held to be true beliefs and understandings, but in practical terms people are people, why invest time in re-examining something that everyone just _knows_ to be true -- it has been around for 80 years, right? Living with accepting long held beliefs would be perfectly fine -- _if_ we were in a utopian situation where we could explain everything and there are no mysteries. But we're not there yet, are we? 1365:

mass of some magical substance that is absolutely incompressible but has mass. You keep dropping this substance into the big mass, little by little. Finally you stop when the escape velocity on the surface of the mass is c minus some tiny amount. Then you drop your clock onto the surface of the mass. You look at the clock. What does it do? It's moving veeeery veeeery slowly. It's almost red-shifted to black, but you can just make it out. Time has actually slowed down in there. You can make it slow down by an arbitrary amount by how much mass you dropped into the pile. You can make it slow down by so much that 10^10^10 years must pass before the clock can advance one nanosecond. Now suppose it's sitting there like that, all stable, time slowed down very much -- then you "turn off" the magical property that makes it uncompressible. Say you turn off the stasis field. :^) (reference to

903:

running on a treadmill. This emission can take an arbitrarily long time, which is why you continue to see an image of infalling objects arbitrarily long after they were dropped. Light emitted from within the horizon is sucked into the singularity despite propagating away from it at C, as the swatch of space it's moving in is moving FTL relative to an outside observer. If you try to lower something through the horizon on a cable that's stationary relative to a distant observer, your cable disintegrates when it touches the horizon because the force-carrying particles binding it together are sucked away. While this is an incomplete way of looking at a black hole (it doesn't give you the insights looking at it as curved spacetime does), it's correct as long as you define your coordinates properly, and is good for giving a qualitative feel for what's happening. --

1898:

time to gain enough mass to form an event horizon -- you agree. 2) Instead of incompressible sphere, make it normal neutrons that you've dropped onto it one by one until it starts to collapse on its own -- This time the surface of the sphere will have downward velocity as it collapses. However as it approaches the point where an event horizon forms, time is dilating so it takes longer and longer (outside) for the collapse to progress. Yes in its reference frame it takes finite time to complete the fall, but it still can't complete because time progression slows to zero asymptotically. 3) Then generalize the concept to any infalling mass with arbitrary starting velocity and configuration. Whenever an event horizon _would_ form, it is also dilating time in such a way as to retard the formation.

1799:

same effects as GR under less extreme conditions (i.e. match all of the experiment data that currently supports the GR equations), and 3) provide some kind of explanation as to why you feel the principles the GR equations embody (that C is always measured to be a given value regardless of reference frame, and that inertial and gravitational acceleration are indistinguishable) don't hold for the cases where your equations violate them. People have _tried_ doing this, sometimes with interesting results ("doubly-special relativity" is a really neat idea, for instance), but saying "I think this looks nicer" doesn't cut it, as the equations of GR weren't just pulled out of thin air. It takes more than handwaving to back up a claim that they don't apply.

1390:, just as holding you still on the surface of the earth requires acceleration to warp your worldine into a non-geodesic path. The violence of the acceleration required directly correlates with the depth in the hole's gravity well; start freely falling, and no matter what altitude you start at, you cross the horizon in a finite length of time from the point of view of an observer falling with the collapsing surface, and at the point of crossing, have received signals corresponding to a finite span of time passing in the outside universe. Drop a reflective ball into the black hole, and shine a timing signal at it, and the reflected signal you get back never passes a certain time code (from 1894:

that my understanding of time dilation on the surface of a massive body was correct, which I think you're confirming. So now I understand your argument against my scenario is that the infalling mass would already have velocity -- it's not starting from a stationary state. The fact that it has this downward velocity then means it will take a finite amount of time to complete its fall, in its reference frame. I think that wouldn't change anything--as the mass gets denser and the escape velocity gets closer to 'c', time dilation must increase. It would just move faster towards a state of suspended animation, if that makes any sense.

1535:

why can't a time warp effectively stop time completely? Yes, it's a finite length of time to fall all the way in, but in that reference frame time just stops advancing. Suppose you have a mass. The mass is so great that at some point away from the center, the escape velocity is very close to 'c'. At that point time has slowed down -- whether or not something at that point is "standing" on the mass itself and enjoying the acceleration, or whether it is free-falling. You can tell time has slowed down because a pulse of light sent from that point still has to climb out of the gravity well and get red-shifted.

1728:

is true the other way around, in other words the light from the fellow astronaut, the other stars, the tourists, etc etc would hit the astronaut in a smaller and smaller amount of time, so for the astronaut falling in, would the outside universe seem to get brighter and brighter? and as he approached the event horizon, and the entire future of the universe flashed before his eyes, would it simply become a extremely bright flash? Would it be imperceptible, sufficient to give him a nasty sunburn, or enough to vaporize him? I'm inclined to say vaporize, but I may be off-base here as well.

2018: 105:

galactic nuclei % Active galaxy Radioastronomy % Radio astronomy M87 % Elliptical Galaxy M87 Bulge ! Disambiguation Page Particle accelerators % Particle accelerator John Wheeler % John Archibald Wheeler Scout rocket experiment % Gravity Probe A Red-shift % Redshift Theory of Relativity % Theory of relativity Chaos ! Disambiguation Page Media % Mass media Marble (toy) % Marbles Reissner-NordstrÃ¶m metric % Reissner-NordstrÃ¶m black hole Occam's razor % Occam's Razor Dark-energy star % Dark energy star IMBHs % Intermediate-mass black hole Dark-energy star % Dark energy star

860:

from the clock your image is carrying doesn't tell me what time you are experiencing in my reference frame when I receive the light - it tells me what time you were experiencing _when you emitted the light in the image_. This is a very important distinction. Depending on what convention you use to define how you measure when a distant event occurred, you get different answers about when exactly the horizon was crossed, but you cross it, and the black hole forms, in finite time even from an outside observer's point of view. See point 3 on the FAQ linked from the bottom of

1988:

hole. The black hole only exists as long as sufficient matter continues to fall into it. All I can say is AFM's theories match what I'd rather have for the underlying machinery for the universe, such as 1) No singularities, 2) No big bang ever occured, 3) Red shift in distant objects is not caused because they're receding rapidly, 4) Quasars are not especially bright, they're much closer than originally assumed, 5) Dark matter is a myth made up to prop up incorrect theories, 6) Elegance + simplicity backed up by empirical evidence.

1805:

nonrotating spherically symmetrical collapsing body, any given layer of matter doesn't care whether or not an event horizon has formed under it yet, only how much mass is under it, so if you accept that this is what the diagram looks like with an event horizon in place, you're going to have a hard time justifying a statement that it's not what happens during implosion to a black hole. If you instead dispute that this is what happens in the scenario where an event horizon has already formed, we're back to my first paragraph.--

1656:

amount of time doesn't mean that amount of time is guaranteed to pass in that reference frame. Example: The 1979 movie "The Black Hole", has a run time 98 minutes according to imdb. If I watch 60 minutes of the movie then pause my dvd player forever, what do I know? It's a 98 minute movie, therefore it must complete in 98 minutes according to time within the movie? That's irrelevant if I never push play again. The characters in the movie would be unable to detect that time has stopped, they'd be completely unaware of this.

1902:

complete its fall to a point mass. I say "That's correct, but that doesn't mean it will really happen because the advance of time itself can stop for all practical purposes." The math describing the reference frame of the infalling mass will involve a function of t. At t(X) this happens, at t(Y) this happens, at t(Z) this happens. But at the same time t just isn't advancing happily. While t goes from Y to Z, the universe outside will have withered and burned out and died, and still t won't have reached Z.

1215:

where some of the laws of physics break down. As for time, the relative rate of time flow for objects at the singularity is undefined. It could be considered the endpoint of the infalling object's worldline (as there is a well-defined time of impact from the infalling object's point of view), but my understanding is that this is a somewhat misleading conclusion to draw (as the impact event's spacetime coordinates aren't well-defined from an external observer's point of view).

1645:

infalling object, for example). I'm not going to try to "prove you right" unless you can present reasons beyond just aesthetic ones as to why you consider GR to be in error in the way that you propose. The burden of proof is upon the person making the most extraordinary claim (in this case, that the predictions of GR don't hold, in a regime where it looks like they should). Also, be aware that you can sign your posts with four ~ marks to produce a timestamped signature. --

158:

signals would be able to propagate completely across the hole between computations, making it the ultimate serial computer. Systems that weren't as compact (i.e., that weren't black holes) would have to have some degree of parallel computation if performing at their peak theoretical capacity, which limits the types of problems that you can solve. To the best of my knowledge, nobody's actually found a plausible way to make black holes perform useful computation. --

1816:

sufficiently uncompressible such that I can keep packing them together until I create a nonrotating, spherical mass with an escape velocity just one iota less than 'c'. Can you picture that? Time is slowed down vastly on the surface of that sphere. By adding mass I can arbitrarily slow down time on the surface. Couldn't I then add enough mass such that for all practical purposes time has stopped on the surface? Tell me what's wrong with this picture?

31: 997:

close with an orbiting object as you can lowering an object on a rope - inwards of something like (4/3) the event horizon radius, tangential motion pushes you inwards instead of outwards, making stable orbits impossible. If you want hard numbers for time dilation in specific scenarios, I'm afraid you're going to have to hunt down an astrophysicist and get them to do the number crunching for you. I can only give the qualitative version.--

899:

signals with it. That is not the case for an infalling object, as a photon sent in after it won't ever reach it. Check the spacetime diagrams on the site I linked above to see why - that's why I linked that site. An observer lowered on a rope to just above the event horizon won't be able to contact someone who fell in previously. They'll instead see the previous victim recede, getting even closer to the horizon.

1747: 2029:. The future is at the top, the past at the bottom. The upper left hand side shows the geodesically complete Schwarzschild solution for a black hole also contains a white hole and, sort of, a wormhole between them. Light travels at 45° angles in these diagrams. The diamond on the left could represent our universe, the one on the right an alternate universe. Unfortunately, it is 1081:

infalling matter bound at the surface of the hole, and that this left an imprint on the outgoing Hawking radiation. The type of solution that seems to be in vogue now is to find some way of showing that the event horizon and singularity never actually form. Hawking claimed to have a proof of this recently, but I don't think it's been universally accepted yet. --

950:, while the object experiencing acceleration has its worldline curved away from the geodesic). Thus, while you can dangle an object on a string over a black hole, pull it back after as much time as you feel like, and have the clock show as little time as you like, this scenario isn't the same as the scenario where you have an object _dropped_ into the hole. 1874:

propose gravity works near black holes, are the things that give me the most concern in this discussion. I _do_ read your examples, and I _do_ understand where you're coming from - it just turns out that that approach to thinking about black holes doesn't quite work, for reasons which I've tried repeatedly to explain to you, and which you can also find at

1333:

acceleration, and that would be what caused the time dilation. My answer to that is this: That would be an *additional* cause for time dilation on the clock. Just being in that place at that time would be enough to dilate time. It doesn't matter if you're firing your rocket to escape or if you're suspended on a string. If you're there you've slowed down.

1345:

spacetime. Light emitted after passing the horizon doesn't reach the outside observer, as the light-cones are warped to point inwards, and light emitted just before crossing it is delayed an arbitrarily long time, giving the illusion of asymptotic approach. This is already described by several people, though it seems that thread has been moved to the

1957:, this is further constrained by the idea of directions on the manifold being "space-like", "time-like", or "light-like", with the easiest way to tell the difference being that in a coordinate system defined on a local approximately Euclidean patch of spacetime, the timelike coordinate has a minus sign in front of it in the equations. 1586:). Both the "frozen star" model, and the reasons why it's an illusion, are well-understood. Because the "party line" description of black holes is derived directly from the equations of general relativity, it is important to understand that your claim that the "party line" description is in error is a claim that 225:

particular, astronomers have been watching stars zipping close to the last stable orbit around the black hole in the centre of the Milky Way for two decades. Hubble doesn't have the resolution or wavelength coverage to look at that, so it doesn't get the benefit of the NASA Hubble public relations department ;-)

647:, but I find it pretty unlikely that anything could break up whatever it really is, or keep it from recollapsing if it did. Certainly antimatter won't do it. While I won't make a prediction about physics and technology thousands of years from now, this sounds even harder than making a stable macroscopic 1554:

Whether or not a black hole continues collapsing into a singularity would not affect any of the observations of black-hole like objects seen with telescopes. This black hole that stops because time has stopped would still, from the outside world, feel, taste, smell, sound and look like someone else's

1364:

Do the math: We all know what the math says -- that the victim falling into the black hole keeps right on going in his reference frame. He doesn't stop. However my point is that that would take an infinite amount of time outside for him to complete the fall. Here's an example. Suppose you construct a

1344:

If you do the math, you find that if you track things from the infalling object's reference frame, you don't end up with a discontinuity until the object hits the singularity itself. The apparent halting of the infalling object from a distant observer's point of view is an artifact of the geometry of

1305:

The gyst of the article above is that for the person falling into the black hole time slows down so much, he can never actually fall into the black hole, even in his own reference frame. His clock will never go beyond time T, and actually he will only reach time T after an infinite amount of time has

1116:

in the strongly-curved spacetime near the horizon. Tunneling, by contrast, would involve the wavefunction of matter in the singularity itself (which is undefined but bounded within an arbitrarily small volume, if I understand correctly). The two are analogous in that the end result of either would be

1069:

I believe this is referring to the "remnant" proposal for what happens after black hole evaporation. The description as-stated at the linked glossary is missing something pretty critical (for one thing, an object with no mass has no gravitational field, and so can't be "contained" by it; for another,

807:

I'm not a scientist, but my understanding is that since you can't say that distant events are simultaneous, you can equally well interpret this as "time slows down for matter falling into the event horizon" and "time moves normally, but the distance gets very large, so you see the matter fall in only

739:

An edit by 130.184.202.187 states that GR prohibits BH formation. This is a misunderstanding of general relativity. By definition, you cannot receive information from inside a black hole, and so information from the event horizon takes an infinite amount of time to propagate away. This is a statement

591:

This is probably an elementary idea, but what if you sent something into a black hole with the sole purpose of destroying it? Say, an advanced bomb or payload of anti-matter. Nothing can escape the event horizon, but if you break it up from the inside, won't the gravimetric forces have to decrease as

2033:

to go, or even communicate, from one to the other. So the matter going into the black hole just goes into the black hole. The more realistic model is the picture on the lower left, which shows a star collapsing to form a wormhole. There is no white hole in this picture. You'll also notice that after

1987:

Christopher: I don't think you've read all his lectures. AFM asserts a black hole is a wormhole to a point elsewhere in the universe, and at that point there is a white hole. All the matter streaming into the black hole ends up spraying out of the white hole. There is no singularity inside the black

1893:

arbitrarily close to the horizon radius, which doesn't happen for any material with finite compressive strength." That sounds to me like a yes response to my incompressible sphere example. Nevermind that real material isn't incompressible, the whole thing is hypothetical anyway. What I was after was

1815:

Christopher, I don't think you're really seeing my point at all. You don't even seem to be reading my examples. You're absolutely certain the common theory is correct and I'm just an ignorant layman that you're not even considering it. Just consider this one single example: pretend that neutrons are

1804:

What the pictures themselves are intended to do is not to prove, but to _explain_ in a layman-accessible manner, what exactly it is that GR describes happening near a black hole. In this case, they say that the collapsing star's matter follows the "infalling object P" curve on the second plot. For a

1501:

The FAQ also says "the Schwarzschild coordinate called t goes to infinity when I go through the event horizon" and "At large distances t does approach the proper time of someone who is at rest with respect to the black hole. But there isn't any non-arbitrary sense in which you can call t at smaller

1453:

Okay, so suppose the reflective ball has a clock inside it and is sending out timestamped light too. So when you look at the pairs of timestamps on the light you get back, the observer timestamp will be associated with an onboard timestamp of at most a certain maximum value? And on the other hand,

1258:

Hello, I am not a user of wikipedia, however, I wished to address something. Because the gravitational pull of the black hole is so strong, if you were to "hover" just outside the event horizon of a black hole, then a form of time dilation would occur and, in essence, because time would be moving so

1038:

This is a misconception. The reason why it turns out to be a misconception are explained above, so I'm not going to spell them out again. The very, very short version is that "it looks like the falling object is still there" doesn't mean it's still there. You have to take light propagation time into

996:

An object tossed into a near-approach orbit around a black hole will experience time dilation both from SR and GR effects, but the amount will be different than that experienced by an object you held stationary (relative to a distant observer) at that altitude. In practice, you can't actually get as

859:

The second version you give is the one that provides the most insight into what's actually happening. If I send a radar pulse down into the hole towards where I see your image, it won't reach you, because you passed the horizon long before I even sent the radar pulse. In other words, the time I read

1873:

The fact that you didn't give a response showing understanding of this explanation the first time around, and the fact that you don't appear to realize that your proposal involves replacing GR as a model of gravity, and the fact that you're unwilling to produce a mathematical description of how you

1863:

to halt the collapse as the mass of the sphere approaches that needed to form an event horizon. This means that at some point you're forced to transition between a "rigid body" scenario and a "freely falling body" scenario for any material with finite compressive strength. If you start with a rigid

1798:

I keep trying to tell you, the only way an effect like that could happen is if the equations of relativity are _wrong_. In order to demonstrate that that is a viable scenario, you're going to have to 1) write new equations that describe the situation you think occurs, 2) prove that they produce the

1787:

The pictures look good, but I don't think they prove anything. It's like you're saying, "Given that the event horizon forms, this is what would happen..." I dispute the event horizon forms in the first place. An infinite amount of time can pass outside and the event horizon is still trying to form.

1727:

The way I think about it, the reason the astronaut gets dimmer is because the same amount of light (or number of photons) is spread over a larger amount of time, such that the # of photons per second that reaches the outside world keeps getting smaller and smaller. I would then assume that the same

1655:

The entire argument against my viewpoint is that from the reference frame of the victim falling into the black hole it takes a finite amount of time for him to fall. I grant that -- that would be the result of doing the math. My point is how you interpret that result. Just because it takes a finite

1644:

What you appear to be failing to realize is that what you're proposing isn't just a different way of interpreting the visible behavior of black holes, but a direct violation of general relativity, with measurable consequences (you see different results when sending time-coded radar pulses after the

1415:

the freezing of time for an object falling in is an illusion. However, it also says that the illusion is caused by the paths of light rays and that it may take an unlimited amount of time for the light rays to get out. If so, how can "Drop a reflective ball into the black hole, and shine a timing

1349:

page linked from the top of this page. Alternative ways of describing this effect are also listed on that page. While originally scientists thought something strange happened at the surface of black holes along the lines of what you describe, this was later shown to be a problem with the coordinate

1242:

You're going to have to reference whatever object you're calling a "grey hole" before I can comment on your third point. For black holes, all that an external observer sees happening is that they merge into one object with the combined mass and angular momentum of the parent objects, and lose a lot

1236:

state, and some of these define their coordinate systems such that time as experienced within this universe starts at a boundary corresponding to the light-cone of the expanding decay region in the parent universe, but this just pushes the problem back, and I'm not sure how rigorous or accepted the

884:

That sounds like what I was saying before: you can interpret it as time slowing down for someone falling into the black hole, it's just that your choice is arbitrary. In one reference frame it takes forever to fall in but the light reaches an outside observer quickly; in another one, falling in is

821:

Ken, that was indeed the argument, but that argument is wrong. If you are falling with the material that will form the black hole and are communicating with me using light signals, then I won't be able to receive any information from you after a certain time, T, on your clock. But you will continue

789:

Yes. Hawking, in a sense, uses this fact to show that in anti-de Sitter space, only geometries in which the black hole never actually forms contribute to the Euclidean path integral. Still, for practical purposes we should clasically still think of the black hole as forming, because, for one, it is

478:

If I understand this correctly, inclusion of Hawking radiation should modify this statement to say that "the sum of the entropy connected to the event horizon's area and the entropy due to the leaving radiation, can never decrease". Right? I think that ought to be mentioned, since it took at least

414:

Any charged object, including a black hole, that undergoes acceleration emits photons as a result of the interaction causing the acceleration. This is due the disturbance the object's charge makes in the field of virtual photons that carries the electromagnetic force. The energy comes from whatever

157:

It's a partly-correct statement, if I understand correctly. The actual idea came up in a number of "limits to computation" articles, with the idea being that a black hole's size was exactly small enough that if it was performing calculations at the maximum rate allowed by its contained rest energy,

2001:

So you're admitting that you think GR is wrong because you dislike it's predictions? Science isn't about picking and choosing how you think the world should operate. We need to look at the evidence, and right now the evidence is that GR is a perfectly good theory within certain experimental bounds

1936:

This is, in fact, nothing of the sort. Try reading it again. The page you link to 1) correctly notes that spacetime is not Euclidean (that's the "not just a big box with three space axes and one time axis" part), and 2) correctly notes that you have several options for defining where the time axis

1897:

With my scenario you don't have any black/white transition. With the traditional scenario the event horizon forms and then things get really crazy once stuff goes inside. Follow this progression: 1) Incompressible massive sphere with escape velocity on surface close to 'c' takes infinite amount of

1617:

Christopher: Thanks very much for your commitment to this discussion. What I'd encourage you to do since you obviously have the theoretical background + math experience is to examine the problem from the point of view of trying to prove me right instead of the opposite. Suppose you succeed -- that

1590:

is in error. There is a large amount of experimental evidence that confirms the predictions of general relativity to considerable precision under less extreme conditions. Certainly, black holes are expected to behave differently from the manner that general relativity predicts, but it's neither in

1534:

Christopher, thanks very much for engaging in this discussion. I don't see much point in my studying the math involved enough to work with the equations and come up with the solution you're describing -- because I'll grant the result is what you're saying. You're saying the party line. I'm saying,

1129:

It is still a tunneling phenomenon. Let me try to explain this. In ordinary non-relativistic quantum mechanics you can have a single particle evolving from state x to y while classically it had to pass through z, even though it lacks the energy to be found at z. We call this tunneling, because the

935:

Couldn't I make the clock come back arbitrarily far in the future, just by firing arbitrarily close to the event horizon? So an object that is outside the event horizon, but close to it, could have its time slowed by an unbounded amount. If the clock is slowed by an unbounded amount when it gets

902:

If you want a different way of thinking about it that might feel more intuitive to you, consider a black hole as "sucking in" space itself. Anything falling in, gets sucked in. The signals they send out take longer than expected to reach a distant observer, because despite travelling at C, they're

880:

That FAQ, which I've seen before, says this: "At large distances t *does* approach the proper time of someone who is at rest with respect to the black hole. But there isn't any non-arbitrary sense in which you can call t at smaller r values "the proper time of a distant observer," since in general

750:

Anon could have been thinking of the recent publication by Chapline which was mentioned in Nature in which he does claim that GR prohibits black hole formation. Perhaps that paper should be mentioned in this article, but only with some strongly worded caveats that the scientific community soundly

560:

To reduce the article's size, I see as one possibility to move the FAQ to a separate page: In fact there is much redundancy (all "What is a ...." questions are explained previously, often with almost identical wording), and even if the FAQ makes up "only" about 2.5 pages in my browser, I think the

271:

The real condition of being inside a black hole was described by Hawking in the 1960s and involves the formation of something called a "trapped surface". Essentially, you can tell a singularity is there (and that you're going to hit it) by drawing a sphere around the singularity and looking at the

104:

LinkFix dump for "Black hole", no edits made: Black hole (disambiguation) ! Disambiguation Page Gravitational field % Gravity Active galactic nuclei % Active galaxy John Wheeler % John Archibald Wheeler Russian (language) % Russian language Supermassive black holes % Supermassive black hole Active

1712:

Well I guess it's time for me to repeat the question then... I'm afraid I don't get it either. I had it described to me this way once, can someone tell me if it's right/wrong? Two astronauts head out to a black hole and one of them jumps in. Well, jumps towards it. Lets say they're both waving at

1519:

I agree that this is an interpretation that is useful for some purposes. However, I disagree with the statement that this interpretation prevents black holes from forming in the first place, which is what started this dispute (anon added their web page with a claim to this effect to the "external

1369:

books). So now the mass starts to fall into itself -- or does it? Time has slowed down already, so it doesn't fall very fast. In fact as it falls, the escape velocity gets closer to 'c'. Closer and closer and closer. But as it gets closer, time is slowing down even more. I submit that no mass can

945:

The difference is that a dropped object is freely falling, while an object tied to the end of a rope (or hovering on a rocket) is not (it's experiencing an accelerating force that exactly cancels the black hole's gravitational acceleration). The worldlines followed are very different (the falling

260:

In Schwarzchild coordinates the radial and time components of the metric change sign once past the event horizon, this implies that you cannot avoid moving in a direction of decreasing r no more than you could avoid moving in a direction of increasing t outside the black hole. r is now a timelike

1901:

There isn't any difference in the math that I'm proposing, there isn't any _different_ math involved, it would just be GR and SR + time dilation + whatnot. The only difference is how you look at the results. You say in the reference frame of the falling matter it takes a finite amount of time to

1659:

Along that same example, suppose after the video passes the 60 minute mark I hit a button to slow down the playback rate by 50%. Then every 5 seconds according to my clock I hit the button again, slowing down playback by 50%. The video will effectively stop. It's always moving forward but it can

1317:

Sources for scientific articles are expected to be from refereed journals, or from well-regarded experts in the field. I'm afraid your personal web page about black holes is neither. Also, the interpretation you discuss is already discussed extensively on the talk page (it's an illusion, and the

1214:

The short answer is that the singularity isn't so much "the disintegration of all matter as we know it", as a point where our mathematical models of black holes produce undefined values. This is usually interpreted as an indication that the models are incomplete, as opposed to an actual location

688:

Apparently you'd see a reverse black hole (a "white hole") as you crossed the event horizon of a proper black hole, since everything entering the black hole behind you would appear to come from a single direction due to the intense curvature of space. As for the "edge" of the (possibly infinite)

556:

I agree to this anonymous and undated comment; but also the main article reaches a critical size. This is especially annoying if someone wants to edit the first lines which are not in a (sub)section, and for reverting (frequent!) vandalism (needs edit of the complete article). OK, it's already a

1763:

I've created two figures that may be useful for a description of events that occur when an object falls into a black hole. These were created using "xfig", so they'd have to be redrawn by someone with decent Photoshop-fu or GIMP-fu before being suitable for use in the article. I hope that these

1701:

After playing around with Knowledge I uncovered a very good reason why this is a perfect place for this discussion. It seems every 2 weeks someone asks this same question that I'm asking. So if it turns out I am incorrect, whatever explanation you can bring to bear on convincing me can be quite

1080:

If I understand correctly, this is not the currently favoured view of what happens, though without a really good treatment of quantum gravity, nobody can really say what _does_ happen. The type of solution I heard most about in years past was to assume that some mechanism kept information about

1011:

Actually, those who say that black holes can exist in a finite time to an external observer are the ones who are misunderstanding GR. In the viewpoint of collapsing matter, only a finite time is necessary for collapse inside the event horizon. BUT ... to an EXTERNAL observer, gravitational time

898:

Time does slow down. If you tie a clock to a rope, lower it down to _near_ the surface of the horizon, then haul it back up, it'll read slower than a clock that you kept with you far from the hole. This is only a meaningful test, however, when you are able to haul the clock back, or to exchange

803:

I think the point was not that you can't receive information from inside a black hole, but rather that as the matter falls in towards the event horizon it never gets there because time slows down for it. So it isn't really a black hole, it's a partially formed black hole. If you fell into the

1558:

This black hole would have no problem with missing entropy -- because the mass that has fallen into the hole to form the hole in the first place is still there, all in its original positions, still in the act of falling in. You can't represent a black hole with just 3 numbers -- mass, charge +

1431:

The reflected signal is received by the distant observer at a time arbitrarily far in the future. The observed _timestamp_ on the returned signal, encoded into the signal at its time of _emission_ never passes a certain finite value, no matter how long you wait to receive the signal. Does this

224:

Please note that there is nothing radically new here. Other black holes were proven to exist in the past -- this is just the latest of many, but it happens to have got a lot of publicity because the NASA Hubble public relations department have made a big deal (in order to help save Hubble). In

1966:

You also seem to be missing the point about what science is all about. Nobody is claiming that General Relativity is a completely correct model of reality. In fact, we know quite well where it breaks down (at the energies at which gravity and the other forces are unified, at particle energies

1670:

General relativity theorists have not interpreted the result to mean that black holes can't form, if that's what you're getting at; only that their collapse can't be fully observed by a stationary observer. Once you let someone fall into the black hole, without ever stopping them, things are

1605:

Perhaps the whole debate is moot. The only picture anyone's ever going to get of a black hole is what it looks like from the outside. I think I'd rather believe in my version of what's inside + be proved wrong later by unshakable evidence to the contrary than blindly just give up because I'm

244:'s edit about falling into a black hole is incorrect or at least incorrectly phrased. The three space-like directions do not become time-like, as general relativity is defined on a metric of a given signature (e.g. - + + +). That doesn't even make sense. What does happen is that in the usual 1702:

useful as a contribution to the article itself -- to deter other people from posing the same question. So it seems like this exercise is actually A Good Thing. If people reading an article are left with the same questions, maybe that means someone should answer the question in the article.

1332:

I read the stuff about if a person were to suspend a clock on a rope down close to the event horizon, then pull it back up, time would pass on the clock, also if the clock were to come back out under its own power. Christopher argued this was not the same because the clock was experiencing

524:

A number of papers have been written about the subject. To the best of my knowledge, none of these are accepted as definitely correct, because without a complete theory of quantum gravity, many approximations are needed in order to model Hawking radiation, raising the possibility that the

919:

Suppose I drop in a clock. But instead of a rope there's a little rocket engine attached which fires when the clock is an inch away from the event horizon, propelling the clock back out. When I get the clock back I'll find that more time has passed in the outside world than for the

1967:

approaching the Planck energy, at the singularity in a Schwarzschild black hole, and at the Cauchy surface in other types of black hole). The problem with your statements has been that you appear to be disagreeing with the majority of scientists in your interpretation of what the

1613:

then the only way anything could make sense is if space warps/stretches as described. But if things can't actually contract past the S.R. because of the time dilation, you don't need to resort to the pathological warping of space -- things never get so far out of hand.

1572:

The main point to get past is this: Couldn't time slow down so much so that even if it takes time X to fall all the way into the singularity, you never actually get there -- you're caught at say X/10 frozen in time. If you can just visualize that you'd see my whole

1054:

Can something about eternal black holes and non-eternal black holes be added to this article or be the subject of a new article? I'd do it, but I'm not knowledgeable enough them. This is part of the missing articles project. Another encyclopedia has a (very short)

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I already _have_ told you what's wrong with that picture, when you first gave an incompressible sphere example. In order to keep your sphere from collapsing, you need to apply an extremely powerful _acceleration_ to its material. This has two effects. First, it

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Hmph. I thought "discussion" meant actual discussion. Don't get into the habit of being a Knowledge Nazi. You'll probably find lots and lots and lots of activity going on that doesn't fit into what people expected when building this thing. Welcome to anarchy.

1454:

if you have a rocket hovering arbitrarily close to the event horizon and you do the same thing, the observer timestamp might be associated with an onboard timestamp of arbitrarily far in the future (depending on how close to the event horizon it's hovering)?

683:

There may be something known as a reverse black hole... Stuff just goes out into the universe again from there. The "Big Bang" may be caused by a reverse black hole in another "universe" which is already there. Anyway, what defines the "edge" of a universe?

822:

to receive information from me after your clock indicates T (until the time you are destroyed by the singularity). I will continue to receive information about you till eternity on my clock, but that information is about you before your clock indicates T.

1502:

r values "the proper time of a distant observer." That seems to imply that there is indeed an interpretation where time slows down infinitely (relative to a distant observer) for an object falling in, but that choosing this interpretation is arbitrary.

415:

potential energy source is being tapped to allow the acceleration. Two co-orbiting charged black holes would have their orbits degrade as a result of this emission, for instance. Even two non-charged co-orbiting black holes will emit orbital energy as

1149:

Any process in quantum field theory involving "virtual particles" is exactly analogous to the tunneling in the non-relativistic case. The virtual particle states are precisely the "forbidden" intermediary states the system seems to tunnel through.

1208:

Welcome to Knowledge. I've moved your comment to a new subsection; you can start one by adding a title heading that ==looks like this== on its own line. If you'd prefer it to be in the "breaking up a singularity" subsection, by all means move it

1012:

dilation approaches infinity as the collapsing matter approaches the event horizon. Thus, to the EXTERNAL observer, the time it takes to actually collapse is infinite. Thus, if the universe really has a finite age, black holes do not exist.

1479:

Yes, that is my understanding of how this type of system works. I'm still waiting for one of the GR physicist lurkers to give a more easily-understood description of these scenarios (I realize that my own explanations are often unclear).

1139:

Quantum field theory is just "ordinary" quantum theory applied to fields. The Hamiltonian has the same form as that of harmonic oscillators. The energy levels are equally spaced and are interpreted as states containing 0, 1, 2,... etc.

959:

Giving a more detailed description would involve drawing diagrams, which I don't have time for this evening. Ask on Wednesday if you're still not sure what I'm talking about, and if the diagrams in the cited web page aren't helping.

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All of the work Hawking has done on black holes would have been an unfortunate waste of time -- just like ancient monks arguing over how many angels can dance on the head of a pin. Yes it's a tragedy but history's full of

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description I'm recalling was. The short answer is that we do not presently have an ironclad theoretical description of a beginning or ending of time that I'm aware of (spacetime is assumed to be a surface without tears).

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of what it means to be a black hole. Nonetheless, just because a black hole cannot be probed doesn't mean it doesn't form. These issues are subtle, but the edit as stated is misleading and doesn't do the issue justice. –

1378:, as I pointed out. If you want a qualitative description, then - as was mentioned in the talk thread I pointed you at already - you have to recognize than an object being _held_ at a distance above the horizon is in a 1888:

You say "If you start with a rigid shell at rest a small distance above the horizon radius, sure, it may take longer for the collapse to start, but it only takes an infinite amount of time if your object starts off

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entropy in that it never decreases; Hawking later showed that this quantity can decrease if entropy is produced elsewhere (i.e. in radiated particles), strongly implying that black hole area (times some constant)

1758:

Exchange of information between an observer O and an object P that is falling towards a black hole's event horizon H. Pulse 1 is returned promptly, pulse 2 is delayed an arbitrarily long time, and pulse 3 never

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It is also relevant to the new Hawking paper, in which his argument appears to be, very roughly, that only evolutions which do not form black holes seem to contribute to the Euclidean path integral for gravity.

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could be solved if you assumed that some type of particle or spatial defect remained after the hole's mass went away, and this object contained all of the information that had apparently been lost by the

1767:

It is important to note that things look very different in different coordinate systems. These figures reflect what seems to happen from a distant observer's point of view, if I understand correctly. --

1285:

Of course. It's easy to forget to include some of the many and strange effects of relativity. I guess that's why there's so many 'wrong' interpretations of black holes (among the general population).

2034:

a certain point, it is impossible to prevent the black hole from forming because you can't get to the event horizon before it has formed. The picture on the right does not show a black hole at all. –

1724:

or the singularity of the black hole? I'm inclined to say the event horizon since no light would escape once he reaches the event horizon (and he would thus tun completely black rather than just dim)

722:

article explain why. Short version is that if you include the original stellar collapse that created the black hole, you can't draw a consistent spacetime diagram of a black hole/white hole pair.--

495:

the key word there is "classical." A "classical" black hole does not radiate, because that's a quantum mechanical process. All the sentence says is that black holes have a property (area) that's

1398:

and do the math yourself, one of the physics experts lurking here can explain it to you, as I've given as good a description as I can without breaking out xfig and drawing a spacetime diagram. --

1224:

that I'm aware of don't define an explicit boundary, instead stopping at the point where our understanding of the physics underlying the model of the universe breaks down (the point at which the

1566:

Lots and lots of contemporary physicists would have to collectively say "Doh!" because they've been buying into and teaching and happily explaining what would have turned out to be a fairy tale.

390:

Well I dont see how a black hole electron can interact with other things as we know real electrons do. For instance how do BHEs emit photons if they're black holes. Don has a lot to explain!

1971:

predict. How the model described by the equations diverges from reality is an open question. What the model itself predicts near event horizons is not. Do you understand this distinction?--

839:

What does it mean to "not receive information", though? If I'm falling with the black hole material and you can't receive any information from me after T on my clock, does that mean that

668:

QG will probably allow for spontaneous break up of a black hole. Black holes can evaporate, so the amplitude for a black hole to emit a mini black hole is very likely larger than zero.

1905:

Anyway my enthusiasm for this debate is waning, as I'm sure yours is also. I don't really have any emotional attachment to this point of view. All I'm really after is the human race

1318:

reasons why it's an illusion are described in detail). Please check talk-page discussion before modifying an article, and please only use refereed sources if it's a science article.

1108:

refers to a particle traversing a barrier due to the fact that its wavefunction is nonzero in the region of the barrier (decays exponentially, as opposed to a sharp cutoff to zero).

1864:

shell at rest a small distance above the horizon radius, sure, it may take longer for the collapse to start, but it only takes an infinite amount of time if your object starts off

930:

I repeat the same experiment, constantly setting the rocket to fire when the clock's even closer and closer to the event horizon. So I keep getting the clock back later and later.

977:

So an object tossed into a black hole in a parabolic orbit whose periapsis is just outside the event horizon, will not experience any slowing of time because it is in free fall?

804:

partly formed black hole, as you approach the event horizon you'd see the black hole finish forming under you. (Hypothetically if it was still emitting something to see it by.)

608:. How do you blow up a singularity? As a rough analogy, if I want to destroy a piece of string, I can cut it up into tiny pieces and scatter them around. But if the string has 1326:

Ok, so I looked here which I presume is the "talk page" and didn't find the extensive discussion. Nor did the word "illusion" appear anywhere. I suppose it does now though...

881:

relativity there is no coordinate-independent way to say that two distant events are happening "at the same time." The proper time of any observer is only defined locally."

706:(time reversal of a black hole post-formation). In practice, it's expected that our predictions of what happened break down past the time when the universe approached the 1582:

to produce the "frozen star" interpretation of black holes, before it was realized that this was just an artifact of the coordinate system he was using (as discussed at

925:

Now I reprogram the engine to fire when the clock is a *half* inch away from the event horizon. When I get the clock back I'll get it back later than in the first case.

612:

to begin with, how am I going to cut it apart? I'm not saying it's impossible, since that's far too strong a word, but I certainly can't picture how you'd go about it. —

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I think the asymptotic time warp to 0 is correct -- it solves so many problems. No singularity, no problem with entropy, etc. You don't need to invent solutions like

842:

you can't receive information from me because time has slowed down for me and falling in takes an infinite time by your clock (though a finite time by my clock), or

845:

you can't receive information from me because although it takes a finite time for me to fall in, the distance travelled by the information gets infinitely large?

248:, the radial and time-like directions exchange. This is called a coordinate singularity, and has nothing to do with the physical situation being described. The 1750:

Distortion of light-cones 1) far from the event horizon, 2) near the event horizon, 3) arbitrarily close to the event horizon, and 4) within the event horizon.

1777:

If new versions of these figures are uploaded, you might want to avoid making the duplicate-word mistake I missed twice on the "radar pulse" filename... --

173:

In a recent Horizon documentary the entropy formula of black holes was given, but their version did not feature the Boltzmann constant k. What is correct?

1859:

to the rigid sphere follows a worldline that lets it intersect the accelerating worldline of the shell of matter at the sphere's surface. Secondly, it

1259:

much slower, it would be like traveling to the future, although in reality you would have just aged more slowly. I feel that this should be mentioned.

187:, the formula is A/4. In the article, it is not written in any particular system of units, hence all the constants (which go to one in Planck units). – 127:

Some physicists, including Stephen Hawking, have recently concluded that black holes could act as natural supercomputers of incredible speed and power.

850:

I was under the impression that these are both equally accurate descriptions, so whether I've fallen in yet depends on what reference frame you pick.

1420:

clock)" be true? The reflected signal should be able to get back an arbitrary amount of time in the future, long past any time code on your clock.

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long after it does". Which means that whether the black hole formed yet is purely a matter of interpretation. Is this anywhere near correct?

1949:, which says that inertial frames that move relative to each other have different ideas of how "space" and "time" are defined (related by the 1030: 272:"congruences" of geodesics going outwards and inwards from the sphere. If they are both contracting, then you know there's a singularity. – 1680:

for discussing changes to the article, and we cannot in any case add claims to the article that are not backed up by formal peer review.

349:

Yes, until there's no more stuff outside the black holes. Then they'll radiate themselves out of existance, but it takes something like

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Someone criticized my adding the above link to the black holes page directly under the external links. Fine, sorry. Someone else wrote:

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In 1971, Stephen Hawking showed that the total area of the event horizons of any collection of classical black holes can never decrease

514:

Seth Lloyd of MIT has a new paper showing that Hawking radiation contains information. So far this is a news article at PhysicsWeb. -

1851:(due to the equivalence of inertial and gravitational acceleration). A freely-falling shell without resistance to compression has a 249: 1569:

How long is the right amount of time for the scientific community to pursue a dead end before backing up and trying something else?

1370:

ever form in such a way that the escape velocity can exceed 'c'. And it takes infinite time to even achieve 'c' escape velocity.

751:

rejects Chapline's hypotheses, methods, and conclusions, and that his model differs with standard physics in foundational ways. -

689:

Universe, I'd put money on the Hubble distance as being the common answer. (where space expands faster than light can cross it).

1732:

I hope my description is right... that's pretty much as complicated as it can be if I'm expected to get my head around it ;) --

1386:

towards the hole (or freely collapsing, if you're considering a shell or uniform sphere of matter). Holding it still requires

479:

me some time to figure out what happened to the (supposedly non-diminishing) event horizon area for a shrinking black hole...

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I'm not sure what the point of the FAQ is - it seems like a less precise summary of the information in the main article...

2017: 1836:

That's exactly the result I'm after -- that time slowing down is a roadblock to further increases in the escape velocity.

1329:

I'm truly looking for enlightenment. Anyone who has any insight as to why my way of looking at is wrong, please explain!

97: 888:

I don't understand the idea that time slowing down is *wrong*, as opposed to a valid, but less useful, interpretation.

1243:

of angular momentum and gravitational potential energy in the form of gravity waves as they spiral into each other. --

38: 1545:

Quasars seem to be strangely bright for their presumed distance -- maybe quasars are nearby partially black holes

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arbitrarily close to the horizon radius, which doesn't happen for any material with finite compressive strength.

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clock), no matter how long you wait and listen to the red-shifted return signals. If you don't want to go to

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Someone else here can probably provide a better answer, but the thing to remember is that what's inside the

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I'd like to pose a hypothetical question: what if what I'm suggesting is actually a reflection of reality?

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Please excuse my intrusion to your facinating thoughts in this area, as I am a relative newbie, however...

774:

what's relevant to the new paper? The statement by anonymous that GR doesn't allow black hole formation? -

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Couldn't a time warp exist such that the forward passage of time, for all practical purposes, just stops?

1022: 1628: 1269: 702:. The big bang could be argued to be the time-reversal of the _formation_ of a black hole, but is not a 419:. Accelerating charges to produce photons just provides an additional loss mechanism in this context. -- 1070:

without a gravitational field, it wouldn't absorb other matter). The idea behind remnants was that the

864:, and check the from the "falling into a black hole" site that used to be linked from this article. -- 1542:

The sun ejects 1/3 as many neutrinos as it should, so our confidence in our theories can't be too high

604:, for example). The mass is actually concentrated at (mathmatically, anyway) a single point, called a 533:

for more information. Discussion of black hole entropy and Hawking radiation is probably best done at

380:

wins, and that's that. So, what's wrong with that? I admit it's a bummer, but other than that... --

1937:

is, constrained only by the geometric properties of spacetime. Point 1) is part of the foundation of

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closer to the event horizon, wouldn't the same be true for objects that fall in without coming out?

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featured article, so we can expect it won't grow much any more, but nevertheless this will happen.

282:

Ok that does sound better. My memory of General Relativity lectures is a bit hazy, I have to say.

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If this is an accurate description, does this mean it would take him an eternity to reach the

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No one has been able to merge general relativity with quantum gravity -- gravitons and whatnot

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I seem to be on the wrong talk page here. Sorry I thought this was Black hole electron land!--

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This page appears to be long enough to create the black hole otherwise known as an archive.

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signal at it, and the reflected signal you get back never passes a certain time code (from

2026: 1592: 644: 561:

density of text is so high that it represents a considerable part of the article's size.—

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at the other end, this turns out not to be the case. Some of the links at the end of the

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so it has been reviewed, but it is fair to say that many physicists are not convinced.

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direction, and t is spacelike. Obviously nothing happens to the θ or φ directions. --

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not yet clear what the Hawking calculation actually means for the real universe. –

714:

doesn't completely hold. As for whether falling into a black hole sends you out a

1578:

I _understand_ the approach you're using - it's the same one originally used by

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If you wish to start a new discussion or revive an old one, please do so on the

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http://www.universetoday.com/am/publish/blue_halo_stars_blackhole.html?2092005

1591:

the way you're describing or for the reasons you're describing (it's because

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is expected to apply). Other models describe the big bang as the decay of a

1826:

Because you couldn't add more mass when there's no time in which to do it?

1945:

instead of a Cartesian-style space. Point 2) is part of the foundation of

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is the disintergration of all matter as we know it, would there still be

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A couple questions, beyond the basic one of "am I completely off-base."

1413:

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/fall_in.html

339:

I think stuff can enter a BH quicker than HawkRad can radiate it away!--

1112:

is a completely different mechanism involving the peculiar behavior of

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years--at that point, the universe will be uniformly-distributed heat,

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of time dilation. Among other things, this means that the matter you

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GR - I like GR. I think if you allow something to contract past the

1350:

system being used, rather than a feature of the horizon itself. See

297:

How can it be that a black hole is an infinite energy/mass sink? At

2016: 1753: 1745: 885:

quick but the light takes forever to reach the outside observer.

1923:. This is a new theory that debunks the whole thing. Big stuff. 311:

I'm not an expert in the area, but you might want to read about

1117:

mass loss from the hole, but that's about as far as it goes. --

25: 1130:

particle appears to "tunnel" through the "forbidden" state z.

1039:

account, and light propagates strangely near black holes. --

639:

blow it apart. Of course, we don't know what singularities

301:

point the mass/energy must escape. Where does it go to?--

600:

of a black hole is not just a really dense ball (like a

434:

Hawking's argument is not represented correctly here.

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This needs added to the Have we found them? section.

204:

http://www.newscientistspace.com/article.ns?id=dn8025

430:

Black hole unitarity paragraph needs to be corrected

198:

Hubble measures first proven black hole in Andromeda

2021:

Penrose Diagrams of various Schwarzschild solutions

1220:As for the "beginning of time", most models of the 443:Also his article has been accepted in Phys. Rev. D 1374:If you want to "do the math", it's right there at 368: 209:http://www.theregister.co.uk/2005/09/21/hot_stars/ 1104:. My understanding is that this is not the case. 1096:The article presently contains a statement that 1764:figures are useful to editors of this article. 1595:effects are expected to become significant). -- 1050:Eternal black holes and non-eternal black holes 525:approximations mangle something important. See 403:It's hard to tell them apart sometimes. ;) -- 315:. The idea there is that the black hole very, 1849:affects the amount of time dilation occurring 914:I hate to say this, but I still don't get it. 8: 2014:Hi David, this is old news. See this image: 1919:Well this is an interesting turn of events. 1660:never pass the 60 minute + 5 second mark. -- 319:slowly evaporates due to quantum effects. — 1941:. This is why spacetime is described as a 1676:Please keep in mind that the talk page is 1671:completely different, as Chris points out. 132:Is this true? I need someone to verify. — 360: 354: 1301:http://www.xdr.com/dash/blackholes.html 1861:requires infinite compressive strength 1551:Gravity waves have never been detected 587:Break up a black hole from the inside? 44:Do not edit the contents of this page. 1878:or in any textbook on the subject. -- 1195:merging supermassive binary grey hole 7: 1618:really would be a step forward :^). 1606:unwilling to work through the math. 1411:According to the sci.physics faq at 710:, so the interpretation provided by 144:Sounds like high quality BS to me!-- 1340:to escape the singularity problem. 256:do not have this kind of behavior. 122:I reverted an edit that said this: 1520:links" section of the article). -- 635:If it's really a singularity, you 98:User:Ambush Commander/LinkFix dump 24: 250:Eddington-Finkelstein coordinates 29: 1984:AFM's new website is up here: 1072:black hole information paradox 535:black hole information paradox 408:08:37, 30 September 2005 (UTC) 398:02:34, 30 September 2005 (UTC) 385:11:09, 29 September 2005 (UTC) 344:10:59, 29 September 2005 (UTC) 334:02:12, 29 September 2005 (UTC) 306:00:48, 29 September 2005 (UTC) 287:14:18, 23 September 2005 (UTC) 277:13:28, 23 September 2005 (UTC) 230:14:39, 22 September 2005 (UTC) 192:14:51, 16 September 2005 (UTC) 178:07:58, 16 September 2005 (UTC) 149:02:25, 30 September 2005 (UTC) 1: 2039:01:08, 17 February 2006 (UTC) 1993:00:43, 17 February 2006 (UTC) 1914:18:52, 30 December 2005 (UTC) 1883:17:50, 30 December 2005 (UTC) 1841:17:03, 30 December 2005 (UTC) 1831:11:11, 30 December 2005 (UTC) 1821:08:01, 30 December 2005 (UTC) 1810:06:50, 30 December 2005 (UTC) 1793:03:26, 30 December 2005 (UTC) 1782:19:57, 29 December 2005 (UTC) 1772:19:30, 29 December 2005 (UTC) 1707:05:09, 29 December 2005 (UTC) 1696:03:46, 29 December 2005 (UTC) 1685:03:42, 29 December 2005 (UTC) 1665:01:22, 29 December 2005 (UTC) 1650:00:50, 29 December 2005 (UTC) 1600:19:01, 28 December 2005 (UTC) 1555:black hole with a singularity 1525:18:11, 29 December 2005 (UTC) 1507:15:42, 29 December 2005 (UTC) 1485:22:06, 29 December 2005 (UTC) 1459:20:49, 29 December 2005 (UTC) 1437:18:11, 29 December 2005 (UTC) 1403:08:09, 28 December 2005 (UTC) 1359:19:31, 26 December 2005 (UTC) 1290:22:05, 20 December 2005 (UTC) 1254:Event Horizon and Time Travel 1248:21:39, 19 December 2005 (UTC) 1202:19:46, 19 December 2005 (UTC) 1086:21:21, 25 November 2005 (UTC) 1064:12:45, 25 November 2005 (UTC) 1044:22:03, 17 November 2005 (UTC) 1002:00:42, 17 November 2005 (UTC) 982:00:18, 17 November 2005 (UTC) 965:23:01, 15 November 2005 (UTC) 941:21:44, 15 November 2005 (UTC) 908:19:17, 15 November 2005 (UTC) 893:18:54, 15 November 2005 (UTC) 869:18:34, 15 November 2005 (UTC) 855:15:45, 15 November 2005 (UTC) 827:12:38, 15 November 2005 (UTC) 813:05:27, 15 November 2005 (UTC) 795:18:40, 15 November 2005 (UTC) 782:22:40, 14 November 2005 (UTC) 769:20:03, 14 November 2005 (UTC) 759:19:22, 14 November 2005 (UTC) 745:17:16, 14 November 2005 (UTC) 727:22:11, 17 November 2005 (UTC) 694:11:57, 17 November 2005 (UTC) 463:Hawking radiation and entropy 424:18:39, 15 November 2005 (UTC) 266:21:42, 28 February 2006 (UTC) 163:21:13, 25 November 2005 (UTC) 138:15:44, August 16, 2005 (UTC) 118:Black holes as supercomputers 114:16:10, August 14, 2005 (UTC) 1976:04:48, 7 February 2006 (UTC) 1928:00:46, 7 February 2006 (UTC) 1737:22:03, 22 January 2006 (UTC) 1432:clarify what I'd written? -- 1354:for a discussion of this. -- 1155:13:19, 6 December 2005 (UTC) 1122:02:37, 6 December 2005 (UTC) 673:21:32, 29 October 2005 (UTC) 656:05:45, 29 October 2005 (UTC) 627:04:38, 29 October 2005 (UTC) 509:22:18, 25 October 2005 (UTC) 486:20:11, 25 October 2005 (UTC) 458:15:16, 17 October 2005 (UTC) 2054: 1742:Potentially useful figures 579:00:04, 17 March 2006 (UTC) 570:13:44, 16 March 2006 (UTC) 2007:00:17, 3 March 2006 (UTC) 1588:general relativity itself 1382:situation than an object 1347:Talk:Black_hole/Archive_1 1186:itself best discribe the 735:GR prohibits BH formation 542:21:38, 2 March 2006 (UTC) 519:21:17, 2 March 2006 (UTC) 246:Schwarzschild coordinates 236:Falling into a black hole 643:are without a theory of 108:Ah... links to fix... — 1182:Would the beginning of 531:trans-Planckian problem 369:{\displaystyle 10^{50}} 2022: 1951:Lorentz transformation 1760: 1751: 1295: 370: 2020: 1757: 1749: 592:the chunks separate? 371: 42:of past discussions. 1876:Schwarzschild metric 1626:comment was added by 1611:Schwarzschild radius 1584:Schwarzschild metric 1396:Schwarzschild metric 1388:violent acceleration 1376:Schwarzschild metric 1352:Schwarzschild metric 1267:comment was added by 1230:theory of everything 1188:edge of the universe 1163:Singularity and time 1020:comment was added by 353: 293:Infinite energy sink 2025:These are called a 1943:Riemannian manifold 1110:Hawking evaporation 1098:Hawking evaporation 698:This is covered at 254:Kruskal coordinates 2023: 2002:and conditions. -- 1973:Christopher Thomas 1955:General Relativity 1947:Special Relativity 1939:General Relativity 1880:Christopher Thomas 1807:Christopher Thomas 1779:Christopher Thomas 1769:Christopher Thomas 1761: 1752: 1647:Christopher Thomas 1597:Christopher Thomas 1580:Karl Schwarzschild 1522:Christopher Thomas 1482:Christopher Thomas 1434:Christopher Thomas 1400:Christopher Thomas 1356:Christopher Thomas 1306:passed "outside". 1245:Christopher Thomas 1228:are unified and a 1226:fundamental forces 1119:Christopher Thomas 1102:quantum tunnelling 1083:Christopher Thomas 1041:Christopher Thomas 999:Christopher Thomas 962:Christopher Thomas 905:Christopher Thomas 866:Christopher Thomas 724:Christopher Thomas 712:general relativity 708:Planck temperature 539:Christopher Thomas 421:Christopher Thomas 366: 160:Christopher Thomas 1921:Time has Geometry 1640: 1559:angular momentum. 1281: 1114:virtual particles 1106:Quantum tunneling 1034: 946:object follows a 527:Hawking radiation 467:It is said that 313:Hawking radiation 169:Horizon confusion 87: 86: 54: 53: 48:current talk page 2045: 2027:Penrose diagrams 1853:different amount 1619: 1260: 1013: 625: 623: 617: 483: 375: 373: 372: 367: 365: 364: 332: 330: 324: 137: 135:Ambush Commander 113: 111:Ambush Commander 68: 56: 55: 33: 32: 26: 2053: 2052: 2048: 2047: 2046: 2044: 2043: 2042: 1969:equations of GR 1907:Figuring It Out 1744: 1679: 1593:quantum gravity 1298: 1256: 1165: 1094: 1059:about them. -- 1052: 1023:130.184.202.187 737: 645:quantum gravity 621: 615: 613: 589: 550: 548:Talkpage length 481: 465: 432: 356: 351: 350: 328: 322: 320: 295: 238: 200: 171: 133: 120: 109: 106: 92: 64: 30: 22: 21: 20: 18:Talk:Black hole 12: 11: 5: 2051: 2049: 2012: 2011: 2010: 2009: 1996: 1995: 1981: 1980: 1979: 1978: 1961: 1960: 1959: 1958: 1931: 1930: 1886: 1885: 1870: 1869: 1834: 1833: 1813: 1812: 1801: 1800: 1785: 1784: 1743: 1740: 1730: 1729: 1725: 1710: 1709: 1688: 1687: 1677: 1673: 1672: 1653: 1652: 1622:The preceding 1603: 1602: 1575: 1574: 1570: 1567: 1564: 1560: 1556: 1552: 1549: 1546: 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1212: 1207: 1206: 1203: 1200: 1196: 1192: 1189: 1185: 1181: 1178: 1174: 1170: 1169: 1168: 1162: 1156: 1153: 1148: 1147: 1146: 1145: 1138: 1137: 1136: 1135: 1128: 1127: 1126: 1125: 1124: 1123: 1120: 1115: 1111: 1107: 1103: 1100:is a form of 1099: 1091: 1087: 1084: 1079: 1078: 1073: 1068: 1067: 1066: 1065: 1062: 1058: 1049: 1045: 1042: 1037: 1036: 1035: 1032: 1028: 1024: 1021: 1019: 1003: 1000: 995: 994: 993: 992: 991: 990: 983: 980: 976: 975: 974: 973: 972: 971: 966: 963: 958: 957: 956: 955: 949: 944: 943: 942: 939: 934: 933: 929: 928: 924: 923: 918: 917: 913: 912: 909: 906: 901: 897: 896: 895: 894: 891: 886: 882: 870: 867: 863: 858: 857: 856: 853: 849: 844: 841: 840: 838: 837: 836: 835: 834: 833: 828: 825: 820: 819: 818: 817: 814: 811: 806: 802: 801: 796: 793: 788: 787: 786: 785: 781: 777: 773: 772: 771: 770: 767: 758: 754: 749: 748: 747: 746: 743: 734: 728: 725: 721: 717: 713: 709: 705: 701: 700:Talk:Big bang 697: 696: 695: 692: 687: 686: 685: 674: 671: 667: 666: 665: 664: 663: 662: 657: 654: 650: 646: 642: 638: 634: 633: 632: 631: 628: 624: 618: 616:HorsePunchKid 611: 607: 603: 599: 598:event horizon 595: 594: 593: 586: 580: 577: 573: 572: 571: 568: 564: 559: 555: 554: 553: 547: 543: 540: 536: 532: 528: 523: 522: 521: 520: 517: 510: 507: 503: 498: 494: 490: 489: 488: 487: 484: 473: 470: 469: 468: 462: 460: 459: 456: 452: 449: 448: 444: 441: 440:for details. 439: 435: 429: 425: 422: 418: 417:gravity waves 413: 412: 409: 406: 402: 401: 400: 399: 396: 395:Light current 391: 386: 383: 379: 361: 357: 348: 347: 346: 345: 342: 341:Light current 335: 331: 325: 323:HorsePunchKid 318: 314: 310: 309: 308: 307: 304: 303:Light current 300: 292: 288: 285: 281: 280: 279: 278: 275: 267: 264: 259: 258: 257: 255: 251: 247: 243: 235: 231: 228: 223: 222: 221: 216: 212: 210: 207: 205: 202: 201: 197: 193: 190: 186: 182: 181: 180: 179: 176: 175:ThomasWinwood 168: 164: 161: 156: 155: 150: 147: 146:Light current 143: 142: 141: 140: 139: 136: 128: 125: 124: 123: 117: 115: 112: 100: 99: 94: 93: 89: 83: 80: 78: 75: 73: 70: 67: 63: 61: 58: 57: 49: 45: 41: 40: 35: 28: 27: 19: 2030: 2024: 2013: 1990:David Ashley 1968: 1925:David Ashley 1911:David Ashley 1906: 1904: 1900: 1896: 1890: 1887: 1865: 1860: 1856: 1852: 1848: 1838:David Ashley 1835: 1818:David Ashley 1814: 1790:David Ashley 1786: 1766: 1762: 1731: 1721: 1715: 1711: 1704:David Ashley 1693:David Ashley 1689: 1662:David Ashley 1658: 1654: 1621: 1616: 1608: 1604: 1587: 1537: 1533: 1504:Ken Arromdee 1456:Ken Arromdee 1417: 1391: 1387: 1383: 1379: 1363: 1335: 1331: 1328: 1325: 1316: 1308: 1304: 1299: 1262: 1257: 1234:false vacuum 1194: 1193:How about a 1187: 1183: 1176: 1172: 1166: 1095: 1075:evaporation. 1053: 1015: 1010: 979:Ken Arromdee 938:Ken Arromdee 890:Ken Arromdee 887: 883: 879: 852:Ken Arromdee 810:Ken Arromdee 762: 738: 681: 640: 636: 602:neutron star 590: 551: 513: 504:entropy. -- 501: 496: 492: 477: 471: 466: 453: 450: 445: 442: 436: 433: 392: 389: 338: 316: 298: 296: 270: 239: 219: 185:Planck units 172: 131: 126: 121: 107: 95: 90:LinkFix dump 65: 43: 37: 1367:Larry Niven 1173:singularity 1152:Count Iblis 824:Count Iblis 670:Count Iblis 606:singularity 455:Count Iblis 36:This is an 2031:impossible 1891:stationary 1866:stationary 1338:Gravastars 1197:? Hmmm.. 1140:particles. 862:black hole 720:black hole 716:white hole 704:white hole 516:MegaHasher 213:detail at 1092:Tunneling 610:no length 96:See also 82:Archive 5 77:Archive 4 72:Archive 3 66:Archive 2 60:Archive 1 1759:returns. 1682:Gazpacho 1678:foremost 1637:contribs 1624:unsigned 1278:contribs 1265:unsigned 1222:big bang 1031:contribs 1018:unsigned 948:geodesic 649:wormhole 482:\Mike(z) 447:see here 438:see here 240:I think 2004:Jpowell 1828:Tzarius 1322:unquote 1287:Tzarius 1171:If the 1057:article 792:Joke137 766:Joke137 742:Joke137 691:Tzarius 378:entropy 274:Joke137 263:Jpowell 189:Joke137 39:archive 1953:). In 1573:point. 1061:Kjkolb 920:clock. 653:SCZenz 641:really 506:SCZenz 405:SCZenz 382:SCZenz 1563:that. 1313:quote 1209:back. 776:Lethe 753:Lethe 651:. -- 637:can't 493:think 284:Rnt20 242:Rnt20 227:Rnt20 16:< 2036:Joke 1633:talk 1418:your 1392:your 1274:talk 1199:Andy 1184:Time 1177:Time 1027:talk 780:Talk 757:Talk 567:Talk 537:. -- 529:and 497:like 317:very 299:some 252:and 1857:add 1734:AK7 1639:) . 1280:) . 1033:) . 576:Kjl 563:MFH 183:In 1635:• 1480:-- 1276:• 1029:• 960:-- 778:| 755:| 502:is 491:I 362:50 358:10 1631:( 1620:— 1272:( 1261:— 1190:? 1179:? 1025:( 1014:— 764:– 622:龜 619:→ 565:: 474:. 329:龜 326:→ 50:.

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