0000000000529136
AUTHOR
André Füzfa
Fully relativistic non-linear cosmological evolution in spherical symmetry using the BSSN formalism
We present a fully relativistic numerical method for the study of cosmological problems using the Baumgarte-Shapiro-Shibata-Nakamura formalism on a dynamical Friedmann-Lema\^itre-Robertson-Walker background. This has many potential applications including the study of the growth of structures beyond the linear regime. We present one such application by reproducing the Lema\^itre-Tolman-Bondi solution for the collapse of pressureless matter with arbitrary lapse function. The regular and smooth numerical solution at the center of coordinates proceeds in a natural way by relying on the Partially Implicit Runge-Kutta algorithm described in Montero and Cordero-Carri\'on [arXiv:1211.5930]. We gene…
Nonlinear cosmological spherical collapse of quintessence
We present a study of the fully relativistic spherical collapse in the presence of quintessence using on numerical relativity, following the method proposed by the authors in a previous article [Phys. Rev. D 91, 024025 (2015)]. We ascertain the validity of the method by studying the evolution of a spherically symmetric quintessence inhomogeneity on a de Sitter background and we find that it has an impact on the local expansion around the center of coordinates. We then proceed to compare the results of our method to those of the more largely adopted top-hat model. We find that quintessence inhomogeneities do build up under the effect that matter inhomogeneities have on the local space-time, …