Numerical Relativity As A Tool For Computational Astrophysics

TL;DR

This paper reviews the use of numerical relativity as a computational tool in astrophysics, highlighting recent advances in simulating black hole and neutron star phenomena with high-performance computing.

Contribution

It introduces the Cactus code, a new parallel computational framework for 3D simulations in general relativistic astrophysics, enabling more detailed studies of compact objects.

Findings

Enabling full 3D simulations of black hole and neutron star mergers.

Development of the Cactus parallel code for relativistic astrophysics.

Discussion of future directions in computational relativity.

Abstract

The astrophysics of compact objects, which requires Einstein's theory of general relativity for understanding phenomena such as black holes and neutron stars, is attracting increasing attention. In general relativity, gravity is governed by an extremely complex set of coupled, nonlinear, hyperbolic-elliptic partial differential equations. The largest parallel supercomputers are finally approaching the speed and memory required to solve the complete set of Einstein's equations for the first time since they were written over 80 years ago, allowing one to attempt full 3D simulations of such exciting events as colliding black holes and neutron stars. In this paper we review the computational effort in this direction, and discuss a new 3D multi-purpose parallel code called ``Cactus'' for general relativistic astrophysics. Directions for further work are indicated where appropriate.