COLLOQUIUM 2026

Unveiling the gravitational-wave background with pulsar timing arrays

SpeakerProfessor Michele Vallisneri, ETH Zurich, Switzerland
Date/TimeWednesday, 11 Feb, 3pm
LocationLT 31
HostAsst/Prof Alvin Chua

Abstract

In 2023, multiple pulsar-timing-array collaborations reported evidence for a low-frequency background of gravitational waves. The amplitude and spectral shape of the background are consistent with emission from the population of supermassive black-hole binaries at the centers of galaxies, but more exotic sources are not excluded. I will explore the collection and analysis of pulsar-timing-array data, the key findings reported so far, the implications for our understanding of galaxy evolution and black-hole populations, and the future of this emerging field as more data are collected and more sensitive radio-telescopes enter operation.

Biography

Michele Vallisneri is the Professor of Gravitational Physics in the Department of Physics at the Federal Institute of Technology (ETH) in Zurich, Switzerland. Previously he was a Senior Research Scientist at the NASA Jet Propulsion Laboratory. Prof. Vallisneri is a leading expert in observational gravitational-wave astrophysics. His research has contributed to the measurement of the gravitational-wave background from supermassive black hole binaries, and he leads the Swiss Data Center for the Laser Interferometer Space Antenna (LISA), a European Space Agency flagship mission.