Giovedì 20 Aprile 2017, ore 11:00 Sala seminari Villa Magliola
Numerical Relativity and Inhomogeneous Cosmological Models
Dr. Eloisa Bentivegna - Università degli Studi di Catania
Live Streaming: You Tube
The construction of exact solutions of Einstein’s equation is a complex process, which, depending on the context, is tackled with different tools, such as perturbation theory, post-Newtonian expansions, or direct numerical integration. The accuracy of the latter approach, known as Numerical Relativity, is in principle only limited by the availability of computational resources and by the existence of algorithms capable of exploiting them efficiently; in principle, direct integration can therefore reproduce arbitrary relativistic configurations of the gravitational field with arbitrary accuracy. In this seminar, I will present the general aspects of the theory, illustrate some exact solutions obtained recently, representing inhomogeneous cosmological models characterized by continuous and discrete mass distributions, and discuss their dynamical and optical properties. I will then use these solutions as a reference point to estimate the systematic errors associated with some approximations used in cosmology. Finally, I will present a free-software suite which enables the construction of such solutions.