Under the light of primordial black holes

Primordial black holes are an exceptional problem to search for new physics, between general relativity, quantum mechanics, particle physics and cosmology. I draw some perspectives for studying those fascinating astrophysical objects. First, by using the cosmic-rays that should be emitted by the Hawking evaporation process. Links between the limits obtained and inflation models are proposed to obtain a very constraining upper bound on the power on small scales of the very early Universe. This region is totally out of what can be probed by the CMB and the LSS. The endpoint of the evaporation is studied in string gravity and primordial black holes are considered as a candidate for cold dark matter in the framework of broken scale invariance models. Finally, in scenarios with a low Planck scale (with large extra dimensions) the production of black holes with colliders is considered. I show that quantum gravity effects (Gauss-Bonnet coupling) could be exhibited by the LHC. Some perspectives related with the cosmological constant and with extremely high energy cosmic-rays are drawn. (author)