Black hole formation in a contracting universe

Understand

We study the evolution of cosmological perturbations in a contracting universe.

• We aim to determine under which conditions density perturbations grow to form large inhomogeneities and collapse into black holes.
• Our method consists in solving the cosmological perturbation equations in complete generality for a hydrodynamical fluid.
• We then describe the evolution of the fluctuations over the different length scales of interest and as a function of the equation of state for the fluid, and we explore two different types of initial conditions: quantum vacuum and thermal fluctuations.