Evolution of a mass-less test scalar field on Boson Stars space-times

Understand

We numerically solve the mass-less test scalar field equation on the space-time background of boson stars and black holes.

• In order to do so, we use a numerical domain that contains future null infinity.
• We achieve this construction using a scri-fixing conformal compactification technique based on hyperboloidal constant mean curvature foliations of the space-time and solve the conformally invariant wave equation.
• We present two results: the scalar field shows oscillations of the quasi- normal-mode type found for black holes only for boson star configurations that are compact, and no signs of tail decay is found in the parameter space we explored.