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Name: Alex Botvinnik
Status: N/a
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

According to Steven Hawking from "A Brief History...," when two black holes merge, they form one black hole greater than or equal to the sum of the original masses, or simply the equation: M(f) = M(1) + M(2). The generally accepted theory is that nothing can escape from a black hole, not even light. Yet recently I read somewhere that when matter and anti-matter collide in a black hole near the event horizon, the result would be a burst of energy, which may propel something out of the black hole. I theorize this: If you have two black holes, and one has anti-matter of the other, and the two merge, there would be two things: 1) It would result in annihilation of both matter and anti-matter particles, and this would result in the masses being LESS THAN the sum of the two original masses. 2) It may possibly propel something out of the black hole. I conferred with my Physics teacher and he came up with this. If the two black holes merged, one was the anti-matter of the other, the energy would probably not be enough to propel anything out, BUT might break down the local gravitational field, allowing something to escape beyond the event horizon. Does anyone have anything that they might add to this theory that might help backup or disprove it?

Great question! If one was anti-matter and the other was matter, then when they collided they would create annihilation radiation which would convert mass into photons. My understanding is that mass is the source of the distortion of space-time that we call gravity. I do not think that EM radiation can be the source of gravitation which would mean that as the matter and anti-matter annihilated the mass of the black hole would decrease. This would make the event horizon of the object decrease. At some point matter or light might be able to "break down " the black hole. This would be interesting. I would guess that if the amount of matter decreased so much (complete annihilation) the black holes would disappear and then the light could escape.

Sam Bowen

Actually, matter and antimatter really have no meaning inside a black hole. I think, as far as is known, that the conservation laws that prevent matter from being converted into antimatter break down inside of a black hole. I could be wrong on this. Anyway, it does not matter what form the matter is in, it still has the same gravitational effect (even as light), and therefore should remain trapped. Remember that mass and energy are really the same thing, as far as gravity is concerned, and so even when an explosion occurs, there is no change in the total amount of energy (or mass) that is there -a matter-antimatter explosion converts some mass into a whole lot of energy, but the black hole really does not care. By the way, the Hawking radiation that has been discussed involves a very subtle effect - the creation of virtual pairs of particles - one matter, and the other antimatter, just outside the black hole. Virtual pairs normally cannot exist for very long before they must annihilate, since they violate the law of energy conservation. However, if the two particles were energetic enough that one fell into the black hole while the other flew away, the only way energy could end up being conserved is if the black hole itself lost some energy (or mass) in the process. Actually, a very similar thing has been observed to happen with super heavy nuclei - the nucleus is so highly charged that it must always have at least one electron nearby. If this heavy nucleus is created without such an electron, it spontaneously creates an electron-positron pair, with the positron flying off and the electron staying behind, trapped.

Arthur Smith

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