Simulations of gravitational collapse of quantum fields

These are the first numerical simulations of semiclassical collapse of a massless scalar field in four dimensions in spherical symmetry. The codes are written in C. The core idea in the construction of these simulations is the use of a specific quantum state in which expectation values are taken; a coherent state. This allows the semiclassical simulations to straightforwardly connect to classical simulations, as the expectation value of a quantum scalar in the coherent state is exactly equivalent to a classical scalar. Thus, one can construct semiclassical simulations by building upon classical ones, and adding extra quantum mode functions as dynamical variables.