Explore the formation of accretion disks in LIGO black hole binaries through this 32-minute conference talk by Enrico Ramirez-Ruiz from UCSC. Delve into the evolution and influence of circumbinary gas on binary systems, from stellar to supermassive black holes. Examine observational signatures, numerical modeling techniques, and the similarities between massive black hole and stellar binary systems. Learn about the formation of close black hole binaries, accretion during common envelope phases, and the environmental influence of gas on binaries. Investigate topics such as fallback accretion disks, tidal excitation of spiral waves, and the hydrodynamics of binaries embedded in AGN disks. Gain insights into the prospects for electromagnetic counterparts and understanding flow geometry in these complex systems.