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-   -   BH information lose (http://www.physicsforums.com/showthread.php?t=414770)

2keyla Jul7-10 09:54 PM

BH information lose
 
Let me preface by apologizing if this isn't posted in the correct forum... If it isn't, please point me to the correct forum and I'll gladly re-post.

Why is an anomaly like a BH considered a singularity?

Why is a BH not considered to be a super massive object existing in our space-time fabric? So massive and most likely spinning, but not necessarily spinning, to cause light not to reflect back to the viewer. Hence a black hole. Or more appropriately an onyx object.

Here's my question... why are BHs not emitting huge amounts of neutrinos? or are they?

If they are emitting neutrinos wouldn't that exclude them from the "singularity" concept?

zhermes Jul7-10 10:15 PM

Re: BH information lose
 
http://en.wikipedia.org/wiki/Black-hole

Passionflower Jul7-10 10:47 PM

Re: BH information lose
 
Quote:

Quote by 2keyla (Post 2791604)
Let me preface by apologizing if this isn't posted in the correct forum... If it isn't, please point me to the correct forum and I'll gladly re-post.

Why is an anomaly like a BH considered a singularity?

It is not. A black hole and a singularity are not synonyms.

According to the theory of general relativity a black hole, as modeled by the Schwarzschild or Kerr solution must have a singularity. It is simply a consequence of the theory.

Quote:

Quote by 2keyla (Post 2791604)
Why is a BH not considered to be a super massive object existing in our space-time fabric? So massive and most likely spinning, but not necessarily spinning, to cause light not to reflect back to the viewer. Hence a black hole.

Well that is pretty much what it is.

Quote:

Quote by 2keyla (Post 2791604)
Here's my question... why are BHs not emitting huge amounts of neutrinos? or are they?

Because the gravitational force is so strong that even light cannot escape from it.

Chronos Jul8-10 12:03 AM

Re: BH information lose
 
Neutrinos cannot escape from inside the event horizon. The have no more priveleges than photons. Particles do escape a black hole at the event horizon. Pair production at the quantum level occasionally allows real particles to escape. It's called Hawking radiation. The negative energy part of the equation is absorbed by the black hole causing an effective loss of mass, and after a virtual eternity, evaporation of the black hole.

Passionflower Jul9-10 07:24 PM

Re: BH information lose
 
Quote:

Quote by 2keyla
Why is a BH not considered to be a super massive object existing in our space-time fabric? So massive and most likely spinning, but not necessarily spinning, to cause light not to reflect back to the viewer. Hence a black hole.

One corrective comment: whether something is a black hole or not does not only depends on its mass. A black hole does not have to be very heavy, one can have a very light black hole as well. Whether an object is a black hole depends on the size of its surface area in relation to its mass, electric charge and angular momentum.


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