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have angular momentum.

- Is the angular momentum an integer or half an integer? Or neither/both?

- What happens when two black holes are exchanged?

François

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- Thread starter franoisbelfor
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- #1

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have angular momentum.

- Is the angular momentum an integer or half an integer? Or neither/both?

- What happens when two black holes are exchanged?

François

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I am not completely sure though, as this is out of my league.

- #3

Borek

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Angular momentum and spin are different things.

Disclaimer about the league holds here as well.

Disclaimer about the league holds here as well.

- #4

Fredrik

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this is because of virtual particles they have been discussed many times in many forums but briefly, they are particle/antiparticle pairs that are created in a vacuum with no energy from quantum fluctuations that usually annihilate and return the borrowed energy but, just one of these particles can cross the event horizon leaving the other and it appears as if the black hole is radiating particlesfrom what I've read, Black Holes emit fermions. I am not completely sure though, as this is out of my league.

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have angular momentum.

- Is the angular momentum an integer or half an integer? Or neither/both?

- What happens when two black holes are exchanged?

François

Can you first of all tell if, say, the earth is a boson or a fermion?

If you can't answer that, or if the question really is meaningless, then how are we supposed to be able to answer something that is even MORE EXOTIC?

Zz.

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- #8

Fredrik

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I think his point was that according to the theory, the properties of a black hole are completely represented by a short list of numbers: mass, charge and angular momentum. The only other objects in the universe that can be characterized this way are elementary particles. So black holes have a lot in common with particles, while the Earth doesn't.Can you first of all tell if, say, the earth is a boson or a fermion?

If you can't answer that, or if the question really is meaningless, then how are we supposed to be able to answer something that is even MORE EXOTIC?

- #9

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Can you first of all tell if, say, the earth is a boson or a fermion?

The Earth is a boson. Fermions are only the same after rotations by 4 pi, the Earth is the same after 2pi, I would say.

François

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The Earth is a boson. Fermions are only the same after rotations by 4 pi, the Earth is the same after 2pi, I would say.

François

Really! Yet, I can distinguish the earth rather easily and track it's path, etc. Did you not care about the indistinguishibility of bosons when you make such a statement? What statistics did you use to arrive at such a conclusion? It certainly isn't QM.

Can you also please tell me the "spin quantum number" of the Earth?

Zz.

- #11

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I think his point was that according to the theory, the properties of a black hole are completely represented by a short list of numbers: mass, charge and angular momentum. The only other objects in the universe that can be characterized this way are elementary particles. So black holes have a lot in common with particles, while the Earth doesn't.

So can a lot of classical objects!

Yet, the term "angular momentum" for quantum particles take on a DIFFERENT meaning than classical objects. Did we settle already that classical angular momentum is the SAME thing as quantum angular momentum? Since when?

And since when can a non-coherent composite object be considered a boson or a fermion? Look at any composite bosons that we know of. What is the MAIN criteria for that whole entity to be considered as a composite boson? Need an example? Look at the Cooper pairs.

Zz.

- #12

Fredrik

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That its Hilbert space is the representation space of an irreducible representation of the Poincaré group?And since when can a non-coherent composite object be considered a boson or a fermion? Look at any composite bosons that we know of. What is the MAIN criteria for that whole entity to be considered as a composite boson?

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- #14

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How about if we consider black holes that are really mini, instead of a classical ones...

- #15

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That its Hilbert space is the representation space of an irreducible representation of the Poincaré group?

Then show me the difference between an "ordinary" liquid helium He4 in "normal" phase versus the superfluid phase. Why does it have to go below some critical temperature for the BE condensation to take place if "the whole earth" is a boson already?

Zz.

- #16

Fredrik

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- #18

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if gravitons exist, they are bosons with a spin of 2

- #19

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He4 is "matter", and so are Cooper pairs. Yet, they are BOSONS. This fact already falsified what you wrote.

Zz.

- #20

malawi_glenn

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How about if we consider black holes that are really mini, instead of a classical ones...

how big are classical black holes?

- #21

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Are Boson's the only particle that would allow a Black Hole to collapse down to a singularity?

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