There ARE no black holes !?

[Uncle Fester]

Hawking spoils the black hole party again.

First they evaporate and now they don't even exist... well that is what you might have noticed lately in the boulevard press headlines, until you read on from a better source:



It is all about avoiding information loss
What he actually claims is that the event horizon doesn't exist.

In place of the event horizon, Hawking invokes an “apparent horizon”, a surface along which light rays attempting to rush away from the black hole’s core will be suspended. In general relativity, for an unchanging black hole, these two horizons are identical, because light trying to escape from inside a black hole can reach only as far as the event horizon and will be held there, as though stuck on a treadmill.

Maybe a black hole could be basically just an over dense neutron star with enough gravity time dilation to make things look like they stand still at the event horizon. A neutron star in suspended animation

Unlike the event horizon, the apparent horizon can eventually dissolve. Page notes that Hawking is opening the door to a scenario so extreme “that anything in principle can get out of a black hole”. Although Hawking does not specify in his paper exactly how an apparent horizon would disappear, Page speculates that when it has shrunk to a certain size, at which the effects of both quantum mechanics and gravity combine, it is plausible that it could vanish. At that point, whatever was once trapped within the black hole would be released (although not in good shape).
If Hawking is correct, there could even be no singularity at the core of the black hole. Instead, matter would be only temporarily held behind the apparent horizon, which would gradually move inward owing to the pull of the black hole, but would never quite crunch down to the centre. Information about this matter would not destroyed, but would be highly scrambled so that, as it is released through Hawking radiation, it would be in a vastly different form, making it almost impossible to work out what the swallowed objects once were./

I have always disputed singularity as I discussed with Trash in the Tytower thread, this sounds more reasonable to me
So by definition a black hole would really not exist if anything could get out if this new horizon collapses and this radiation is actually scrambled information of what has fallen in, so better a grey hole !

[Thomas Ennis]

Hawking is a brilliant man; no doubt, but I sometimes wonder if he writes this stuff just to get a rise out of the community. His theories have always been educated, though radical. I can only imagine what's out there in the universe. The only problem is, we may never see any of these theories play out.

Mathematics is an extremely valuable too in determining things like this, but I wonder how far math can take us. The only way to know for sure, is keep exploring the heavens. Scientific advancement will; without a doubt, continue to increase at a phenomenal pace. If I had a time machine, I would certainly travel back and witness the big bang. The only thing is, would there be any place for me to witness it from?

[trash]

It may be a recent thought Nomeat because of the gas cloud that was recently spat out of Sagittarius A.

There seems to be little doubt from the observational evidence that black holes exist.
And they were predicted mathematically before they were realised.
Though their nature may not be as expected.

I don't think this is out of character for Hawking and cosmologists. Fishing for thoughts can be a good way to the little guys to front up some interesting ideas.

I've mentioned something similar in previous posts Nomeat. The readers might remember I asked how matter falls in.
It appeared that most people didn't understand the nature of the question. "Things fall because they just do." That's what most people understand.
In order for material to fall into a black hole, it has to lose the kinetic energy it carries or be on a direct course with the black hole.
In which case the black hole picks up the kinetic energy of the object it consumed.

The recent gas cloud basically couldn't fall in because it was heated by the accretion disk where it picked up energy and was spat out.
Though, it's likely that some material already in the disk paid the price for the escape of the cloud.
What will be interesting is what the verdict will be on this gas cloud. Did it pick up energy ? Was it gravitationally sling shotted or captured or broken up.

And of course, there may be a possibility that what we know as a black hole is something completely different.

[gordon_s1942]

I can follow Hawkins line of reasoning that what goes in may indeed come out but as Doc McCoy said, 'Not as we know it, Jim.'

Its perfectly feasible that if you were able to take a common ordinary house brick and grind it down to its base atoms, there is no way you could guess its original form so why cant a 'Black Hole' do the same IF the pressures stated occur within its self do just that and emit whats left out into the space around it?
So unless there is a way to 'go-see' for ourselves, it will remain just another theory.

Other than all the pretty pictures taken by the Hubble Telescope that delight and dazzle one and all, I havent seen one benefit to us here on Earth for what it cost to build, launch and operate.

[Thomas Ennis]

Gordon, you do have a point about the Hubble. The pictures we see are doctored as well. I do wonder if we really can do anything more from here? Seems to me; that the only way to find anything out for sure, would be to send an object into space. With the distances involved, we'd most likely be extinct before any really valuable information ever reached us.

With the economy in such a dreary state in the US, space exploration is going to be on the back burner for a while. The government needs a 15 billion dollar aircraft carrier and welfare checks before our tax money can go anywhere else. I don't know what the economy is like in Australia, but you guys and gals from down under have a better chance of sending something into space than we do.

[Tiny]

no mate, we're in the same boat, billions in debt, couldn't afford to send a chook into space at the moment.

[trash]

Its perfectly feasible that if you were able to take a common ordinary house brick and grind it down to its base atoms, there is no way you could guess its original form so why cant a 'Black Hole' do the same....

You misunderstand what it is meant by existence or "information" Gordon.
When you speak of the "ordinary house brick" grinding it down is not what happens in a black hole.
When you disintegrate the brick, you're still following what we generally describe as newtonian physics. Given that we know the position of each atom and it's velocity we can put the house brick back together (in theory) or more correctly describe with precision exactly what the house brick was.

Newtonian physics of course doesn't work when we describe the universe more precisely on the quantum scale.
When dealing with black holes, this is the scale at which we work. The logic is just reduced to a simple atom or electron.

Electrons are very good examples because they're relatively simple particles.
When we drop an electron into a black hole, it's mass grows by one electron. This electron also has quantum spin and parity.
Now if we drop another electron in, the mass grows again by one electron.
Next we drop in a positron. Does the mass decrease or increase by one electron ? (Given the the mass of a positron is the same as an electron)

Then we do the same thing again, but this time the positron we drop in is entangled with an electron in the real universe.
Does the material swallowed contribute to the evaporation of the black hole in any way?
What it means is the very information of the material that fell in is lost.

Originally (pre 70's) it was considered that the information was lost. The only information that remained about any particle that fell in was the memory of it's mass which now contributes to the black hole.
Stephen Hawking then came along and suggested that when entangled particles fell in, the information from inside the black hole escaped through quantum entanglement which isn't restricted to the speed of light. The matter and energy which escapes is Hawking radiation.

So the real question is which of these two theories is correct ?

While it may seem cosmologists really don't know and seem to flip and flop on which is theory is correct.
This is a good thing because you're able to change your position and go back and realise mistakes or improve theories with new information.

Looks like there is a show on SBS at the moment dealing with the said gas cloud.
Watching it now. It looks like a good show for us ordinary folk

[gordon_s1942]

Two opposing Theories, a Million Scientists and you expect an answer ????
Basically there are no correct answers because for every answer arrived at, someone will come along and espouse an other possibility.

[trash]

There are correct answers, just sometimes it takes a little while for the right one to crystalise.
Disagreement isn't a bad thing in science. It's a good thing because it means that many different trains of thought are looking for the correct answers.
They flip flop between theories based on evidence and this shows that they're prepared to consider everything. But at the same time their minds are not so open so as their brains might drop out onto the floor.
Just look at tytower and myself. TT puts forward a new idea. I consider it and weigh up the evidence prepared to change my view. It his theory fits, then I modify or change my thinking.
If however TT is wrong, evidence or observation doesn't support what he is saying, then I will point out where he has made a mistake.
Now in return a scientist would consider my reply and say, "ah yes. I see my mistake." or "I didn't know that, but now I do, I can go back and think about it and come back again with a better theory."
There isn't a scientist who doesn't do this.
Tytower on the other hand solves the problem by getting angry. He blames me for making his universe wrong. Which is fair enough. As a living god, it's my duty to torment lesser life forms.

I think about somebody very clever like Sir Isaac Newton. Does any of us think that he didn't make mistakes and use trial and error.
Now imagine you could go back in time and suggest the theory of relativity to him. Would he dismiss you as a crackpot OR would he consider it and look for evidence ?

It's not so much that the previous theories were wrong. Newtonian physics still works just fine. But the new theory is just better.
It builds on old knowledge.

Look at the steady state and big bang theories. The steady state theory worked well for a while but then theoretical evidence started to suggest that this might not be the case.
Then Hubble discovered the universal red shift and Wilson & Penzias the CMB. This pretty much was the end of the road for steady state theories.
But then while measuring the gravity of the universe looking for evidence of a "big crunch" or a "big fade" as the universe coasts out forever, we find something completely unexpected.
Universal acceleration (dark energy) which will result in a "big rip". Completely unexpected.
The entire universe will end when it is torn apart at the planck scale, like the event horizon of a black hole.

The end of the universe will occur "everywhere" just like the start of the universe also occurred "everywhere".

We wouldn't know this if we hadn't investigated the state of the universe in the first place. The steady state theory was a stepping stone on that path to discovery.

[trash]

Tytower on the other hand solves the problem by getting angry. He blames me for making his universe wrong. Which is fair enough. As a living god, it's my duty to torment lesser life forms.

The logic of this argument is, TT is angry because I'm a god.
Or I'm not a god, and therefore he's just an angry moron.

I'm sure there's other definitions which we can use to describe this, but the evidence will always point to the truth.

[lsemmens]

Here's another piece of "logic" for your argument. "TT is angry because you think you are a god", or, "TT is angry because he isn't a god" or, maybe, just maybe, "neither of you are gods" this, is more likely, because "I am a son of God, and neither of you are my dad"

[Tiny]

Now now, were starting to fall into another black hole called religion. That is way off topic here!!!

[myoldhk]

Isn't a black hole the void in your guts when you FART and BURP at the same time. haha

I BLAME PREDICTIVE TEXT FOR MY SPELLING

[thomas pendrake]

It has long been understood that quantum effects allow for leakage from black holes. Remember that the universe is probably a black hole. If there was indeed a "big Bang" the universe must be a black hole. And by the way, the cosmological red shift was discovered long before the Hubble telescope. Basic research is the basis for all research. If we give up basic research the well of future development will quickly run dry.

[trash]

And by the way, the cosmological red shift was discovered long before the Hubble telescope.

Haha, I think you misread what was said.
"Then Hubble discovered the universal red shift and Wilson & Penzias the CMB.".
Hubble = Edwin Hubble.
Who do you suppose the telescope was named after ?
And who do you suppose might have discovered the cosmic red shift ?
Maybe I should have said, "Ed discovered the cosmic red shift." ?