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nomadreid
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In his popular-physics book "The Universe in a Nutshell", Hawking presents the creation/annihilation of virtual particle pairs in two ways:
(1) one particle has positive energy, the other negative energy, and
(2) a matter/antimatter pair.
This leads to the obvious conclusion that he is identifying antimatter as particles with negative energy, out of a sort of Dirac sea. However, this identification makes me wonder:
(a) on one side, negative energy results in repulsive gravity, but
(b) on the other side, antimatter is supposed to have the same gravitation as matter.
Something is not right. What?
While I am at it, another question on such pairs, whatever they are. One explanation for Hawking radiation is that one of the particles, either the one with negative energy and/or the antimatter one, falls into the black hole, while the other particle, matter with positive energy, escapes as radiation. However, these explanations never mention why it is the antimatter and/or particle with negative energy that falls into the hole, and the other one escapes, instead of the other way around. Why?
Thanks in advance.
(1) one particle has positive energy, the other negative energy, and
(2) a matter/antimatter pair.
This leads to the obvious conclusion that he is identifying antimatter as particles with negative energy, out of a sort of Dirac sea. However, this identification makes me wonder:
(a) on one side, negative energy results in repulsive gravity, but
(b) on the other side, antimatter is supposed to have the same gravitation as matter.
Something is not right. What?
While I am at it, another question on such pairs, whatever they are. One explanation for Hawking radiation is that one of the particles, either the one with negative energy and/or the antimatter one, falls into the black hole, while the other particle, matter with positive energy, escapes as radiation. However, these explanations never mention why it is the antimatter and/or particle with negative energy that falls into the hole, and the other one escapes, instead of the other way around. Why?
Thanks in advance.