Black hole bound on the number of species and quantum gravity at CERN LHC

In theories with a large number N of particle species, black hole physics imposes an upper bound on the mass of the species equal to M₏₋₀₍₂₊/N. This bound suggests a novel solution to the hierarchy problem in which there are N10^32 gravitationally coupled species, for example 10^32 copies of the standard model. The black hole bound forces them to be at the weak scale, hence providing a stable hierarchy. We present various arguments, that in such theories the effective gravitational cutoff is reduced to ₆M₏₋₀₍₂₊/N and a new description is needed around this scale. In particular, black holes smaller than ₆^-1 are already no longer semiclassical. The nature of the completion is model dependent. One natural possibility is that ₆ is the quantum gravity scale. We provide evidence that within this type of scenarios, contrary to the standard intuition, micro-black-holes have a (slowly fading) memory of the species of origin. Consequently, the black holes produced at LHC will predominantly decay into the standard model particles, and negligibly into the other species.