Mapping the Gravitational Wave Background: Unveiling Cosmic Structures with Black Hole Mergers

This study by Semenzato and colleagues investigates how gravitational waves from supermassive black hole binaries might reveal patterns in the universe's large-scale structure (LSS). Using simulations, they show that filtering out loud sources uncovers a gravitational wave background (GWB) that aligns with galaxy clustering, suggesting that the GWB could serve as a cosmic map of LSS. They conclude that cross-correlating GWB maps with galaxy distributions in future pulsar timing array experiments could offer unique insights into the structure of the universe and the distribution of dark matter.