Do black holes have multiple singularities?

[Ivan Seeking]

Black holes are staples of science fiction and many think astronomers have observed them indirectly. But according to a physicist at the Lawrence Livermore National Laboratory in California, these awesome breaches in space-time do not and indeed cannot exist.

Over the past few years, observations of the motions of galaxies have shown that some 70% the Universe seems to be composed of a strange 'dark energy' that is driving the Universe's accelerating expansion.

George Chapline thinks that the collapse of the massive stars, which was long believed to generate black holes, actually leads to the formation of stars that contain dark energy. "It's a near certainty that black holes don't exist," he claims. [continued]

http://www.nature.com/news/2005/050328/full/050328-8.html

http://xxx.arxiv.org/abs/astro-ph/0503200

 

[SpaceTiger]

I can buy that there's something other than a black hole causing the phenomena we see, but this:

these awesome breaches in space-time do not and indeed cannot exist.

That makes it smell like bull****.

 

[Enos]

If anything, Black holes only exist. Relativity uses observations to explain almost all phenomena and observations rely on the event which occur in the past and the probabilities of the future. It's impossible to observe the present(existence).

 

[Berislav]

From the paper:

...what time does one mean when one writes down the Schrödinger equation...

Aren't the problems in his calculations arising merely from using non-relativistic quantum mechanics in a relativistic theory?

The paper also seems to neglect the fact that the apperent singularity at the event horizon is only geometric. The problem resovles when one uses the Kruskal-Szekeres coordinates.

 

[Chronos]

Looks like a cowpie to me too - despite the authors impressive record of published papers...

 

[chronon]

I would agree with Chapline that quantum considerations are likely to mean that black holes don't exist, especially since Hawking's announcement of his belief in the conservation of information (see http://www.chronon.org/Articles/blackholes.html). However, I don't find Chapline's paper convincing. He doesn't seem to link to other work on quantum theory in curved spacetimes. Since we don't have a full theory of quantum gravity, any result needs to be seen in the context of other ideas, and Chapline doesn't provide this.

 

[ctrebor]

Black holes certainly exist- what doesn't exist, yet, is the singularity within them. Black holes are thought of as- sort of- "frozen" in time from our viewpoint. See below. Black holes and singularities are two different beasts, though one is a consequence of the other. The singularity is in fact only a potential state.

The nature of the collapse has been described by Kip Thorne in his book Black Holes and Time Warps: Einstein's Outrageous Legacy (Picador 1994);

"There is a great paradox about black holes which is the result of applying relativistic formulas to the theory of the collapsing star, however. The theory of relativity shows that from the viewpoint within our universe- i.e. outside the black hole's event horizon- the star seems to freeze at its critical circumference of the event horizon and go no further. From the viewpoint of an observer on the surface of the star, that is within the event horizon, however, the star would be crushed to a point in a short space of time."

"Like a rock dropped from a rooftop, the star's surface falls downward (shrinks inward) slowly at first, then more and more rapidly. Had Newton's laws of gravity been correct, this acceleration of the implosion would continue inexorably until the star, lacking any internal pressure, is crushed to a point at high speed. Not so according to Oppenheimer and Snyder's relativistic formulas. Instead, as the star nears its critical circumference, its shrinkage slows to a crawl. The smaller the star gets, the more slowly it implodes, until it becomes frozen precisely at the critical circumference. No matter how long a time one waits, if one is at rest outside the star (that is, at rest in the static external reference frame) one will never be able to see the star implode through the critical circumference. That is the unequivocal message of Oppenheimer and Snyder's formulas."

 

[Billy T]

...according to Oppenheimer and Snyder's relativistic formulas ... the star nears its critical circumference, its shrinkage slows to a crawl. The smaller the star gets, the more slowly it implodes, until it becomes frozen precisely at the critical circumference. No matter how long a time one waits, if one is at rest outside the star (that is, at rest in the static external reference frame) one will never be able to see the star implode through the critical circumference. That is the unequivocal message of Oppenheimer and Snyder's formulas."

I agree that one never will see it or anything pass thru the event horizon, and I think you (and they) are correct in one view point, but at least making false implications in another.

The star will disappear from view to observer safely at a distance from the collapse. It last visible light will be a few red photons, then our IR detectors will see it a little longer, but some time later, it will be giving off no radiation and any beam sent to reflect from it will not return. It is "gone" not "frozen" even to an outside observer. - I am no expert, but that is my understanding.

 

[Huckleberry]

http://www.nature.com/news/2005/050328/full/050328-8.html

http://xxx.arxiv.org/abs/astro-ph/0503200

If dark matter is made of matter that travels faster than the speed of light then aren't these newly formed stars basically black holes?

I saw a show "Scientific American" hosted by Alan Alda a few weeks ago. It said that our galaxy is surrounded in a cloud of dark matter and energy. It also said that the outer rim of our galaxy moves slower than the interior and that our solar system moves at about 500 million miles an hour in orbit around the center of the galaxy. I'm not positive, but I thought they said that dark matter and energy is released when atoms are smashed. It crossed my mind, and I know how unpopular this theory is, that if we are moving at 500 million miles an hour at our location in the galaxy then perhaps the outer visible rim of the galaxy is moving +/- the speed of light in relation to ourselves. So dark matter would not interact with us on any level because it doesn't exist in 3 dimensions, has no mass, and thus no energy. But it could interact with matter that is moving within light speed of itself and that matter could then affect us. This would explain the gravitational effects of dark matter, wouldn't it?

What was the question?
Huck

 

[requiem]

Is there really such a thing as a singularity? How are astronomers able to tell that the basis of a black hole is a singularity? What if the basis of a black hole is actually an ultra small (but still dimensional) object consisting of super-dense, super-compact sub-atomic particles? Maybe the famed Hawking radiation is just the black hole expelling extraneous sub-atomic particles (a la neutron stars)? Is there hard theoretical evidence that requires the basis of a black hole to be a singularity? Would the fact that the basis of a black hole is actually dimensional object help any uncertainty involving the physics that occur in black holes?

I seem to have a bad habit of asking questions. Unfortunately, when you don't have the answers, there's not much else to do. I'm extremely sorry if these questions come across as naive in any way.

 

[ctrebor]

Mass of a Black Hole

I agree that one never will see it or anything pass thru the event horizon, and I think you (and they) are correct in one view point, but at least making false implications in another.

The star will disappear from view to observer safely at a distance from the collapse. It last visible light will be a few red photons, then our IR detectors will see it a little longer, but some time later, it will be giving off no radiation and any beam sent to reflect from it will not return. It is "gone" not "frozen" even to an outside observer. - I am no expert, but that is my understanding.

I don't think so- if it was "gone" it would not have mass, charge or spin. I don't think the term frozen is adequate as one no doubt could not see the black hole, let's say, hidden just at the event horizon, but the important point is that there is NOT a singularity in the black hole as seen from this reference frame. The idea that there are millions or billions of singularities all over the universe is erroneous. There may be millions or billions of black-holes but there will only ever be ONE singularity. Just like you go through the pores of an orange and you reach the centre of the orange, but there is only one centre no matter how many pores.

 

[matt.o]

My understanding of the meaning of 'singularity' is that it is not something physical , but a place where our laws of physics not longer work.

 

[Spin_Network]

My understanding of the meaning of 'singularity' is that it is not something physical , but a place where our laws of physics not longer work.

Then do you agree?. that when a physical Law is placed into a singularity, the Law may be rendered, or transformed, to different outcomes, one that is not pertaining to outside the singulrity?..I think is what you are basically stating, so..if a Particle that abides by our 'Physical Law', happens upon a Singularity, say at a BH local horizon, then there may be a process where it emerges in a different form?

I am thinking about a 'known-matter' particle that enters a black hole, but emerges as an 'Unknown-matter' particle.

If a photon enters a singularity, what is the probability it will emerge as a 'photon'?

 

[matt.o]

No, what I am saying is you cannot predict anything using our laws of physics, hence it is pointless talking about the probabilities.

What it means is that our laws don't work, hence we need new ones to explain what goes on in a black hole.

 

[Spin_Network]

No, what I am saying is you cannot predict anything using our laws of physics, hence it is pointless talking about the probabilities.

What it means is that our laws don't work, hence we need new ones to explain what goes on in a black hole.

I agree totally.

 

[tdunc]

From article

"If the dark-energy star is big enough, Chapline predicts, any electrons bounced out will have been converted to positrons, which then annihilate other electrons in a burst of high-energy radiation. Chapline says that this could explain the radiation observed from the centre of our galaxy, previously interpreted as the signature of a huge black hole."

He is talking about those "cosmic jets" isn't he? I always assumed that was due to synchrotron radiation.

 

[Billy T]

I don't think so- if it was "gone" it would not have mass, charge or spin. I don't think the term frozen is adequate as one no doubt could not see the black hole, let's say, hidden just at the event horizon, but the important point is that there is NOT a singularity in the black hole as seen from this reference frame. The idea that there are millions or billions of singularities all over the universe is erroneous. There may be millions or billions of black-holes but there will only ever be ONE singularity. Just like you go through the pores of an orange and you reach the centre of the orange, but there is only one centre no matter how many pores.

On "gone" I agree with you. I should have been more careful in expressing myself. I meant "gone" only in the sense that we could no longer see it (I described how the radiation would become undetectable.) Of course its gravity etc. will be felt.

But this lack of care on my part in expressing myself, combined with the point you are making does raise a very interesting question: Assume that an enormous black hole swallows a galaxy. If to an out side observer, the galaxy is still at the event horizon, years latter, is there a "bump" in the gravitational field of the BH? Do the higher terms in the tesseral harmonics that describe the gravitational structure, reflect the angular distribution of the mass it has "eaten"? I don't know enough to make a guess - perhaps it does.