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Black hole matter/antimatter

by Unredeemed
Tags: black, hole, matter or antimatter
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Unredeemed
#1
Sep11-08, 12:33 PM
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Is matter going into a black hole the same as antimatter leaving one?

This has confused me for a while...

Thanks,
Jamie
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George Jones
#2
Sep11-08, 12:56 PM
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Quote Quote by Unredeemed View Post
Is matter going into a black hole the same as antimatter leaving one?
No.

Matter and antimatter falling into a black hole increase the mass of the black hole. Matter and antimatter "leaving" (Hawking radiation) a black hole decrease the mass of the black hole.
Unredeemed
#3
Sep11-08, 01:02 PM
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But wouldn't the antimatter and matter anihilate one another inside the black hole?

George Jones
#4
Sep11-08, 01:08 PM
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Black hole matter/antimatter

My point was that since matter falling into a black hole increases the black hole's mass and antimatter leaving a black hole decreases a black hole's mass, these two processes are not the same
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But wouldn't the antimatter and matter anihilate one another inside the black hole?
Only if their worldlines intersect inside the black hole. Even if this happens, the mass of black hole remains unchanged from the mass just "before" the annihilation event.
Unredeemed
#5
Sep11-08, 01:11 PM
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Is that due to the conservation of energy and mass?
George Jones
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Sep11-08, 01:20 PM
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Is that due to the conservation of energy and mass?
Yes, this is because of (local) conservation of mass/energy.
wolram
#7
Sep11-08, 01:33 PM
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Quote Quote by George Jones View Post
No.

Matter and antimatter falling into a black hole increase the mass of the black hole. Matter and antimatter "leaving" (Hawking radiation) a black hole decrease the mass of the black hole.
What is this antimatter?
George Jones
#8
Sep11-08, 01:55 PM
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What is this antimatter?
For every particle of matter, there is a corresponding particle of antimatter. The (additive) quantum numbers of an anitparticle have values that ere the negatives of the values of the quantum number for the corresponding particle.

For example, an electron has negative electric charge, and a positron (anitmatter electron) has positive electric charge. If a particle and corresponding antiparticle collide, they annihilate each other, releasing energy.
mheslep
#9
Sep11-08, 04:49 PM
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...For example, an electron has negative electric charge, and a positron (anitmatter electron) has positive electric charge. If a particle and corresponding antiparticle collide, they annihilate each other, releasing energy.
Tangents, if you are inclined:
Assuming the electron and positron are the same thing(? same mass, etc) differing only in charge:
1. Why don't an electron and positron settle into quantum mechanical orbitals about each other similar to the traditional electron and nucleus?
2. If an high energy electron can in fact be made to collide with a (proton based) nucleus, why does it not 'annihilate' some 1/1800 th of the much larger proton?


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