Advancing Multimessenger Astrophysics: New Techniques for Realistic Neutron Star Collision Simulations

by Prof. Etienne Zachariah (Uni Idaho)

Friday 16 Jun 2023, 11:00 → 13:00 Europe/Berlin

Seminar Room 102 (TPI, FSU Jena)

Perhaps the most significant astronomical discovery of our lifetimes, code-named GW170817, resulted from the cataclysmic collision of two neutron stars. This immensely powerful event sent vast amounts of light and gravitational waves hurtling across the cosmos, which were subsequently detected by telescopes and gravitational wave observatories on Earth. Neutron stars, composed of the densest matter in the Universe, are at the heart of this "multimessenger" event, which has dramatically advanced our understanding of how matter and gravity behave under extreme conditions, far surpassing the scope of Earth-based laboratories.

 

To extract science from events like this, we compare observations against theoretical models. Unfortunately, our theoretical models are severely limited both in quality and quantity, 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 multimessenger source modeling, I will outline a new approach aimed at greatly reducing the cost of these simulations. With the reduced cost comes the potential to both perform colliding black hole simulations on the consumer-grade desktop computer, as well as add unprecedented levels of physical realism to colliding neutron star simulations on supercomputers.