Why singularities do not exist

In summary: The photons emitted from the apparent horizon are just as intense as the photons emitted from the absolute horizon. The only difference is that they are red-shifted.
  • #1
Dmitry67
2,567
1
I posted it in SR/GR but probably it really belongs here:

I am looking at the way how Hawking radiation is derived:
http://en.wikipedia.org/wiki/Hawking_radiation

Where can I find more info about it? (for amaters like me)

Formula for the Unruh temperature gives an infinite temperature at the horizon.
At the same time AFAIK the apparent horizon recedes in front of the falling observer.
Also, is my assumption correct that observer sees radiation from an apparent horizon, not from an absolute one?
The Hawking radiation looks very intensive but extremely red-shifted by the gravitation. Like almost infinity devided by almost infinity.

So I wonder how intensive the Hawking radiation is for the freely falling observer.

I can explain my motivation. Non red-shifted Hawking radiation is very intense. So when observer approaches the singularity, singularity is always hidden behind the apparent horizon. However, the horizon it covered with a cloud of hawking particles. These particles (in a frame of a falling observer) are emitted from the horizon but then fall back into the singularity together with the observer.

But the singularity of mass M is represented with the mass of the matter inside the apparent horizon S and the 'cloud' C, M=S+C

While C is almost negligible far from the singularity, it is quite possible that C>S close to it. But then singularity itself does not exist because the cloud 'blurs' the singularity and flattens space-time.
 
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  • #2
Dmitry67 said:
I posted it in SR/GR but probably it really belongs here:



I can explain my motivation. Non red-shifted Hawking radiation is very intense. So when observer approaches the singularity, singularity is always hidden behind the apparent horizon. However, the horizon it covered with a cloud of hawking particles. These particles (in a frame of a falling observer) are emitted from the horizon but then fall back into the singularity together with the observer.

But the singularity of mass M is represented with the mass of the matter inside the apparent horizon S and the 'cloud' C, M=S+C

While C is almost negligible far from the singularity, it is quite possible that C>S close to it. But then singularity itself does not exist because the cloud 'blurs' the singularity and flattens space-time.

So your saying that for the falling observer the photons in the cloud are not observed as they fall into the singularity? But they remain outside the apparent horizon? I'm confused!
 
  • #3
No, no.

At first, as it is well known, the very notion of the 'particle' is observer-dependent, for some observers particles can be real, for others they are virtual, for some observers space is vacuum, for others it is not.

For example, Hawking radiation observed for the outside observer is insivible for the freely falling observer.

I speculate that however freely falling observer observer ANOTHER type of hawking radiation - for HIS apparent horizon (different observers do not agree on the position of the apparent horizon).

As observer falls into black hole, apparent horizon recedes in front of him. So for the falling observer horizon is 'smaller' and emits much more radiation then for an observer 'at infinity'
 
  • #4
Dmitry67 said:
For example, Hawking radiation observed for the outside observer is insivible for the freely falling observer.

This isn't true.
 

FAQ: Why singularities do not exist

1. Why do scientists believe that singularities do not exist?

Scientists believe that singularities do not exist because they violate the known laws of physics, including the principles of general relativity. In a singularity, the laws of physics break down and it becomes impossible to make accurate predictions about what would happen in such a scenario.

2. What evidence supports the idea that singularities do not exist?

There are several pieces of evidence that support the idea that singularities do not exist. One of the main pieces of evidence is the fact that the laws of physics break down in a singularity, making it impossible to accurately describe or predict what would happen. Additionally, observations of black holes have shown that they have a finite, non-zero size, which contradicts the idea of a singularity with infinite density.

3. Could there be other explanations for the observations that currently support the existence of singularities?

While it is always possible that there could be other explanations for observations that currently support the existence of singularities, none have been proposed that fully explain the data. The current understanding of black holes and the laws of physics suggest that singularities do not exist.

4. How do scientists study the concept of singularities if they do not believe they exist?

Scientists study the concept of singularities through theoretical models and mathematical equations. While they may not believe that singularities actually exist, they can still explore and analyze the consequences of such a scenario within the framework of existing laws and theories.

5. Could our understanding of physics change in the future and lead to the acceptance of singularities?

It is always possible that our understanding of physics could change in the future, but it is unlikely that this would lead to the acceptance of singularities. Any new theories or laws would still have to adhere to the principles of general relativity, which currently do not allow for singularities. Additionally, the abundance of evidence that contradicts the concept of a singularity would need to be explained or disproven.

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