The Dawn of Gravitational-Wave Cosmology
Main list: Physics and Astronomy Colloquia
Gravitational waves are ripples in spacetime, produced by the most
violent events in the cosmos: exploding stars, colliding black holes, perhaps even the Big Bang itself. Since September 2015, when the twin LIGO (Laser Interferometer Gravitational-Wave Observatory) instruments made the first-ever direct detection of gravitational waves from the merger of two massive black holes more than a billion light years distant, the LIGO Scientific Collaboration and the Virgo Collaboration have reported the confirmed detection of ten further compact binary mergers - including the merger of two neutron stars detected in August 2017 that was also observed across the entire electromagnetic spectrum. Moreover since April 2019 the LIGO and Virgo detectors have been engaged in their third observing run, with enhanced sensitivity, and during the first four months of “O3” they reported a further 22 candidate detections. The gravitational-wave window on the cosmos is now well and truly open!
In this lecture I will review the latest LIGO and Virgo observations of the mergers of binary black holes and neutron stars – and how these observations are shaping and improving our understanding of strong gravity, cosmology and fundamental physics. I will then outline the gravitational-wave “roadmap” for the coming decades, including the planned LIGO and Virgo observing runs and upgrades, the addition of KAGRA and LIGO India to the ground-based network, the “ third generation” ground-based interferometers proposed for the 2030s and the enormous potential of spaceborne detectors that will probe the lower frequency gravitational-wave spectrum. I will describe how these observations should provide a much deeper and more complete view of the Gravitational Universe over the next two decades, offering new and complementary insights into a wide range of astrophysical questions – from the origin of black holes and the evolution of galaxies to the nature of dark matter and dark energy and perhaps even the fundamental properties of spacetime itself.
Physics Theatre C
October 11, 2019
From: 10h00 To: 11h00
University of St Andrews
The oldest university in Scotland, with international renown for both research and education of undergraduates and postgraduates.