Abstract Details
| Name: Manvendra Pratap Rajvanshi Affiliation: IISER, Mohali Conference ID: ASI2018_1689 Title : Nonlinear Spherical Perturbations in Quintessence Cosmology Authors and Co-Authors : Jasjeet Singh Bagla IISER, Mohali Abstract Type : Poster Abstract Category : General Relativity and Cosmology Abstract : It is well established that the universe is dominated by dark energy. The cosmological constant is consistent with most of the observational constraints on dark energy. There are numerous models of dynamical dark energy where the cosmological constant is replaced by a field or a fluid. It has been shown using perturbation theory analysis that in most such models the fluctuations in dark energy at small scales are very small, perhaps too small to be detected. We present results of a study where we consider the influence of non-linear perturbations in dark matter on the evolution of fluctuations in dark energy. We use Quintessence models of dark energy in this study. Our analysis is fully relativistic and assumes spherical symmetry. Linear perturbation analysis indicates that perturbations in quintessence models of dark energy do not grow at small length scales. In this study, we look at the response of quintessence dark energy to non-linear perturbations in dark matter. We show that at scales much larger than the virial radii of collapsed halos the fluctuations in dark energy continue to be small. At very small scales within virialized halos, dark energy can develop significant inhomogeneities. We show that dark energy perturbations grow at a faster rate than expected in linear perturbation theory. We find that dark energy perturbation remains localized and does not diffuse out to larger scales. We also find that the equation of state parameter changes in response to perturbations in dark matter. |