Blackhole at the center of each galaxy, think again

O really, genius?

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Well... eburacum45 have answered it well.

In fact, that's how accredition disks exist!! How do you think they are formed!?!?!?

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I don't know, eburacum45, the Hawking announcement was in the news and all I know is that he said that Hawking radiation does not happen. It wouldn't drain mass from a black hole if virtual pairs formed at the event horizon anyway. Those are a zero sum game. The one that fell in would add to the mass.

 

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No, that is not the way it is supposed to happen. The virtual particles that form in vacuum, and also at the event horizon, are not just simply matter-antimatter pairs; if they were, they would produce a photon when they annihilated each other anywhere, not just at an event horizon.

No; instead of being just matter-antimatter, they are also a pair of particles with zero net energy; that is to say one particle has positive mass/energy, the other has negative mass/energy. Negative mass/energy particles cannot exist in the real universe except for an infinitesimal fracton of a second before meeting a positive particle and cancelling itself out of existence; but at an event horizon, they are separated irreparably from their positive partner, and fall into the black hole.
As they are negative in mass, they actualy make the hole less massive, while the positive partner becomes real and escapes.
Note that this cannot happen the other way because negative mass particles cannot exist independently. The net evaporation is all positive, leading to evaporation as if the hole had a temperature- which in effect it has.

Hawking's recent pronouncement was really only about information conservation, rather than evaporation; I don't think he said evaporation would not occur, just that information was somehow conserved inside and outside the hole.

 

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Why would the negative mass particles fall into the black hole and not the positive mass?

I can see how information might be conserved. We've all heard of information compression.

 

when the pair of particles are created, they're virtual particles. The BH sucks one of these particles, and the other escapes, becoming a real particle with positive mass. the sucked particle must acquire negative mass, to counter the positive mass of the other particle (conservation of energy must be preserved)

 

I must say you are good at this, Lucas...

 

Thanks, I appreciate the comment

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I thought that negative mass was repelled by gravity?

 

I believe that the point is that virtual particles have neither negative nor positive mass. It isn't until one of the particles is taken by the black hole that the other particle takes on mass.

Negative mass is a contradiction in terms so it can only have positive mass. But, it would seem that the other half, locked away from the normal universe, is able to take on negative mass. And so, in effect, it is as though the black hole spit out the particle with positive mass rather than absorbing a particle with negative mass.

A very slippery concept. It makes sense though. In all the treatments of this I've read before, I don't think that any mentioned negative mass... or perhaps my memory is poor in this. It's been a while since I've looked into Hawking radiation.

Hmm. Although. If neither particle had mass until one was taken out of the universe... then how did the black hole even absorb it? Is it pure chance that the motion of the virtual particles would take one in and the other on an escape route? What's to prevent the black hole from absorbing the remaining particle once it has acquired positive mass? I suppose that somehow during this process it must have gained enough momentum to carry it out of the black hole's grip? How fast does it move on average? Is it a photon so it would be traveling at the speed of light? Or is it an electron? I've always thought of quantum virtual particles as electrons (an electron and a positron). A photon's anti-particle is another photon, right?

Hmm.

And about Hawking's latest announcement. Has he still not made it clear what he was saying then? Didn't he just give a short statement with the intent on being more clear on the subject later?

 

It acquires negative mass once it's inside the event horizon, and then it cannot escape the BH

 

Addendum:

The particle cannot be a photon as photons have no rest mass....


Addendum the Second:

Hmm.
I suppose that even photons are captured by black holes and relativity shows that gravitational lensing occurs... So. Rather than thinking in terms of gravity, one should think in terms of warped space-time.

However. Why wouldn't a negative mass particle be ejected from the black hole? Wouldn't a negative mass particle roll uphill? Up the gravity well, rather than down? What's to prevent the negative mass particle from escapeing? Gravity? Why would gravity act this way? Gravity pulls both positive and negative mass? And even no mass? This would suggest that gravity has nothing to do with mass at all....

(I know my thinking has taken a wrong turn somewhere down the line...)

 

Do you know what it's going to be like to find any details about Stephen Hawking's refutation of his own theory? One article I found said that scientists are frustated at the lack of details.

Photons don't have to have a rest mass to have gravity or to act as if they have mass.

 

U dont seem to get it DO U.

If most of the stars are binary systems then there should have been large no of BH-Star binary systems. Now comming to the part of what U got my wrong; If had there been large no of such systems then we should have seen those fantastic thing about Light bending and space bending and what not, but as we know ....


BTW what is accredition disks, I hope If BH exist then in future we find such binary systems with new powerfull telescopes to test the BH effects on the stars passing by behind the BH.

 

Here is some evidence for gravitational microlensing events associated with black holes;
hope this helps
http://bustard.phys.nd.edu/MPS/aas195_bennett.pdf

Actually close binaries like Cygnus X-1 are probably quite unusual; the sort of star that becomes a black hole is more than ten times the Sun's mass, and I believe they are more often solitary.

 

The papers in which Hawking introduced the concept of Hawking radiation can be found in Internet

"Black hole explosions"
http://www.aeiveos.com/~bradbury/Authors/Astronomy/Hawking-SW/BHE.html


"Particle creation by black holes"
http://projecteuclid.org/Dienst/UI/1.0/Summarize/euclid.cmp/1103899181

 

I believe TruthSeeker meant accretion disc. Now you have some idea what it is like to try to understand your mix of typograhical errors and text-speak.

eburacum, your suggestion that the more massive stars tend to be solitary is logical: a collapsing cloud that does not split into smaller vortices would concentrate its mass in a single star. However, can you cite any observational data that supports this. I was looking for some recently in connection with another matter, without success.

 

We're absolutely sure that there is a black hole in the center of our galaxy,because in the center there are no binary systems,plus the extreme velocity of these stars is just tremendous.

 

But U havent yet seen a Star passing behind a BH, right ? When U do, U will realize that ....

 

you will realize what? that the light is bent around the edge in a sort of halo? we know this already. all light is bent around the black hole, anything that has ever passed near, behind, into, is still in that halo of light. the light is trapped there. we never see anything go into the black hole because of the distance between us and it; the light is 'trapped' there.

 

Not directly, and it appears that I might have been wrong. It seems that large stars often form in stellar nurseries in groups of four or so (the Trapezium is a good example) and gradually kick out members of their group over time, leading to various so-called 'runaway stars'. But some groups remain closely associated (or perhaps have not had time to split up yet) and so many giant stars are multiple.
Here is a straw poll of giant stars showing their (currently understood) status, taken from Jim Kaler's website;
Eta Car Binary
Regor Binary
Iota Ori Quaternary
Naos Singular
Menkib Singular
Alnitak Binary
Alnilam Singular
Saiph Singular
Kappa Cass Singular
Zeta-1 Sco Singular
Zeta Per Trinary
Tau Cma Quinary
Gam Ara Binary
P Cyg Singular
Omi-2 Cma Singular
Aludra Singular
Rigel Trinary
Polis Quinary

Most of these are quite widely separated, but some (such as Tau Cma) are tightly knit. As most of these stars are reasonably distant it is likely that some of the singletons are close binaries; but it is also possible that some of these associations will fall apart before the star(s) go supernova.