Black hole quantum mechanics in the presence of species

作者：Dvali Gia^*; Gomez Cesar; Luest Dieter

来源：Progress of Physics, 2013, 61(7-8): 768-778.

DOI：10.1002/prop.201300002

Recently within the context of a microscopic quantum theory, the Black Hole%26apos;s Quantum N-Portrait, it was shown that continuous global symmetries are compatible with quantum black hole physics. In the present paper we revise within the same framework the semi-classical black hole bound on the number of particle species N-species. We show that unlike the bound on global charge, the bound on species survives in the quantum picture and gives rise to a new fundamental length-scale, L-species = root(N-species) L-P, beyond which the resolution of species identities is impossible. This finding nullifies the so-called species problem. This scale sets the size of the lightest quantum black hole in the theory, Planckion. A crucial difference between the gravitational and non-gravitational species emerges. For gravitational species, the lightest black holes are exactly at the scale of perturbative unitarity violation, which is a strong indication for self-UV-completion of gravity. However, non-gravitational species create a gap between the perturbative unitarity scale and the lightest black holes, which must be filled by some unitarity-restoring physics. Thus, self-UV-completion of gravity implies that the number of non-gravitational species must not exceed the gravitational ones.

• 出版日期2013-7-1