ITR: MHD Simulations in Full General Relativity

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

Under this award, numerical tools will be developed for the study of astrophysical systems involving relativistic gravity, strong electromagnetic fields, and rotation. These tools will include computer codes for evolving fluids and electromagnetic fields in a fixed gravitational field, codes for evolving the relativistic gravitational field itself, and a combined code that will evolve gravitational fields with both material and electromagnetic sources. Tools for verifying the accuracy of the integrations will also be developed. The codes will be optimized for use on the latest generation of supercomputers, publicly released, and made available within the scientific community. In the course of developing these codes, computational scientists will be trained at the undergraduate, graduate, and postdoctoral levels. The codes will also be applied by the developers to problems at the forefront of astrophysics and gravitation physics research. This work is motivated by a number of astrophysical systems, including: accreting black holes and neutron stars; coalescing binary neutron stars and black holes; rapidly rotating neutron stars formed in core-collapse supernovae; and collapsing supermassive stars. Taken together, these objects are the focus of a large fraction of current astrophysical research. They are the likely source of detectable gravitational waves, powerful X-ray emission, and gamma-ray bursts. So far, however, they have resisted understanding because the underlying physics of the fluid, the electromagnetic field, and the gravitational field is complicated, nonlinear, and time dependent. Only numerical integrations can unlock the fundamental physics of black hole accretion, test scenarios for the generation of gamma-ray bursts, and generate more accurate predictions for gravitational waveforms from coalescing compact binaries. The required numerical methods do not yet exist; they will be developed under this award.