TAPIR Seminar

In person: 370 Cahill. To Join via Zoom: 868 5298 8404

ABSTRACT: Gravitational wave radiation is only unambiguously defined at future null infinity - the location in spacetime where light rays arrive and where global properties of spacetimes can be measured. Within the context of numerical relativity simulations of compact binary coalescences, one way to reach future null infinity and extract signals there is by evolving the interior Cauchy data outward on characteristic slices. This is Cauchy-characteristic evolution, the current state-of-the-art approach to obtain gravitational waves at future null infinity. I will talk about an alternative method: evolution on hyperboloidal slices, which are spacelike and smooth everywhere, but reach future null infinity. Conformal compactification is a suitable approach to hyperboloidal free evolution that will be used to illustrate the setup, as well as its advantages and challenges. After a brief review of another way to tackle hyperboloidal evolution, namely the dual foliation method, I will present some first results in spherically symmetric configurations, showing the potential of the hyperboloidal method. I will finish with an update on current ongoing work towards 3D evolutions.