Next-Generation Simulations of Binary Black Hole and Neutron Star Mergers
Prof. Zachariah Etienne
Department of Physics
University of Idaho
Perhaps the most significant astronomical discovery of our lifetimes, GW170817, involved the collision of two neutron stars. This extremely violent event launched tremendous amounts of light and gravitational waves into the universe, which were detected by both telescopes and gravitational wave observatories here on Earth. Because neutron stars contain the densest known form of matter in the universe, this single "multimessenger" event marked a watershed moment in our understanding of how matter and gravity behave at their most extreme, far beyond what we can study in terrestrial laboratories. To extract scientific insight from events like this, we compare observations against theoretical models. Unfortunately, our theoretical models are severely limited in both their accuracy and their coverage, and there is a critical need to improve them. Such improvements pose a key challenge to computational astrophysics, as our most detailed models require expensive supercomputer simulations that generate full, non-perturbative solutions of the general-relativistic field equations (numerical relativity). After a gentle introduction to multimessenger astrophysics and the challenges associated with modeling multimessenger sources, I will outline a new approach aimed at greatly reducing the cost of these simulations with multi-patch, multi-coordinate numerical grid structures. With the reduced cost comes the potential to perform binary black hole simulations on consumer-grade desktop computers, as well as to add unprecedented levels of physical realism to binary neutron star simulations on supercomputers.
Hosted by Prof. Mathews