Supermassive black hole mergers are among the most energetic cosmic events, releasing gravitational waves with energy comparable to all the stars' light in the Universe over a short period. These mergers significantly influence the mass distribution of supermassive black holes across the cosmos. However, visual evidence of such events is scarce due to uncertainties about the electromagnetic emissions accompanying gravitational waves.

To address this, new General Relativistic Magnetohydrodynamics (GRMHD) simulations are underway. These simulations provide insights into the environments of supermassive black hole binaries as they merge. Using advanced computational techniques to model accretion dynamics and magnetized gas flow around spinning black holes, these simulations reveal gas flows near binary systems.

The simulations offer crucial data for predicting the electromagnetic and gravitational wave signatures of black hole binaries, informing future observation strategies with missions like LISA, PTA, and other upcoming facilities. Efforts continue to refine computational tools to enhance our understanding of supermassive black hole interactions in binary systems.