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In the Master of the Universe programme it was described that black holes gave off radiation as a result of the negative mass part of a particle/anti-particle pair being drawn into the black hole leaving its partner to rush off. But wouldn't something with negative mass be repelled by gravity rather than attracted?
Prof Pethica: Both particles and anti-particles have positive mass. These virtual pairs are produced by quantum fluctuations, an important property of the vacuum. There are no particles known to have negative mass, so the question of repulsion doesn’t arise.
There are theories about negative mass, first due to Bondi, but there is no evidence it applies to real world matter. Hawking showed that negative energy is required for closed timelike curves. (see The Future of Spacetime, Norton 2002) This is part of the reason why time machines are not going to happen. You can find out more on this at the usual encyclopaedic websites and search engines.
There are theories about negative mass, first due to Bondi, but there is no evidence it applies to real world matter. Hawking showed that negative energy is required for closed timelike curves. (see The Future of Spacetime, Norton 2002) This is part of the reason why time machines are not going to happen. You can find out more on this at the usual encyclopaedic websites and search engines.
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