Abstract

While several promising candidate supermassive black hole binaries have been identified, more realistic physical modelling of these systems will be necessary to confirm their identity and perform robust searches in the era of big-data astronomy. Unfortunately, the large range of temporal and physical scales and wide parameter space have historically made their modelling prohibitive when performed via full 3D general relativistic magnetohydrodynamic simulations (3D-GRMHD).I will first demonstrate the necessity of this type of modelling, despite its complexity and computational expense, and briefly describe the novel numerical tools we employ. I will present our recent 3D-GRMHD simulations which extend longer in duration than comparable prior models and achieve higher resolution and global realism, made possible by using our new multi-domain/multi-physics code, PatchworkMHD. With these improvements we have found unexpected 3D hydrodynamical and magnetic behaviour that is guiding us towards unique binary observational signatures. In ongoing and future time-domain observational surveys like Vera Rubin Observatory’s LSST , these unique signatures will be key to confirming the identity of binary black hole systems and securing them as a cornerstone of multi-messenger astrophysics.