3 ms·

Can you tell us these predictions, please? Is there a way to check them without creating a black hole?

• raattgift 11y ago
  Not trivially, no. I'll try a not-very-technical answer, since I guess that's what you're looking for. However the main problem is a length/energy correspondence. In quantum mechanics you probe shorter length structures by scattering particles with higher energies. At ultra high energies this produces a shower of daughter particles which carry kinetic energy away, and this process should continue to arbitrarily high energies. More energy in the scattering event produces more daughter particles, which evolve unitarily. In general relativity, when you scatter sufficiently energetic particles, the energy density in the area of the collision is greater than that needed to form a black hole; an event horizon forms around the scattering particles. More energy in the scattering event produces a larger black hole, and we don't know how to preserve unitarity for black holes. Evaporation of small black holes does not produce the same daughter particles as predicted by quantum mechanics. There are other related problems as well, especially in the early hot dense phase of the universe. We do not have the ability now to produce scattering energies of the magnitude necessary to probe the different predictions; we also so far don't have a way to observe natural occurrences of sufficiently high energy interactions at the present time, and might not for many years.