Search for Gravitational-Wave Background in Pulsar Timing Array

Explore the latest developments in the search for gravitational-wave backgrounds using pulsar timing arrays in this 49-minute conference talk. Delve into the recent simultaneous releases from major observatories, including the North American Nanohertz Observatory for Gravitational Waves, European Pulsar Timing Array, Parkes Pulsar Timing Array, and Chinese Pulsar Timing Array, which provide strong evidence for a random signal consistent with a gravitational wave background. Examine how detecting different gravitational wave polarization modes can be used to test gravitational theories in a model-independent way. Learn about the significant Bayesian evidence for scalar transverse polarization modes found in data from pulsar timing arrays, including NANOGrav's 12.5-year and 15-year datasets. Understand the implications of these findings, suggesting that current pulsar timing array data may not yet provide substantial evidence for the definitive detection of gravitational waves.