Simulating Extreme Spacetimes with SpEC and SpECTRE

Gravitational wave science requires high-fidelity numerical simulations of the expected merger events. The Simulating eXtreme Spacetimes (SXS) collaboration has managed the development of two distinct codes for this purpose: (i) the Spectral Einstein Code (SpEC) based on pseudospectral methods, and (ii) an open-source code SpECTRE, an hp-adaptive discontinuous Galerkin scheme that also includes a sub-cell finite volume scheme in regions of strong shock formation that is ideally suited for multi-scale, multi-physics problems. SpECTRE targets problems in multi-messenger astrophysics, including neutron star mergers, core-collapse supernovae, and gamma-ray bursts. It runs at petascale and is designed for future exascale computers. Our weeklong program includes two contemporaneous activities: (i) a focused SpEC and SpECTRE code developers meeting and (ii) a SpECTRE workshop. The code developers' meeting will bring together researchers who are actively developing these codebases. The SpECTRE workshop aims to provide graduate students, postdocs, and faculty with the tools needed to install, run, and contribute to the open-source code SpECTRE. Our SpECTRE workshop will cover topics such as the generalized harmonic formulation of the Einstein field equation, general relativistic hydrodynamics, the discontinuous Galerkin method with finite volume sub-cells, the Cauchy characteristic extraction method, installing, running, and visualizing numerical simulations, and how to get involved with code development.