Seminars

QG seminar

Title
Testing General Relativity with Gravitational Waves
Speaker
Vitor Cardoso (CENTRA, IST, Lisboa)
Date & Time
Tuesday, September 26, 2017, 5:00 p.m.
Place
ES035
Abstract
Two pivotal breakthroughs in physics have just celebrated their centennial: the discovery of the Schwarzschild solution, describing a non-rotating black hole, and Einstein's prediction of gravitational waves. Gravitational waves offer a unique glimpse into the unseen universe in different ways, and allow us to test the basic tenets of General Relativity, some of which have been taken for granted without observations: are gravitons massless? Are black holes the simplest possible macroscopic objects? do event horizons and black holes really exist, or is their formation halted by some as-yet unknown mechanism? Do singularities arise in our universe as the outcome of violent collisions? Can gravitational waves carry information about the nature of the elusive dark matter? In this talk, I will describe the science encoded in a gravitational wave signal and what the upcoming years might have in store regarding fundamental physics and gravitational waves.

KMI theory-QG-C joint seminar

Title
An astrometric search method for individually resolvable gravitational wave sources with Gaia
Speaker
Christopher Moore (CENTRA, IST, Lisboa)
Date & Time
Tuesday, October 17, 2017, 3:00 p.m.
Place
ES635 (KMI Science Symposia)
Abstract
Gravitational waves cause the apparent position of distant stars to oscillate with a characteristic pattern on the sky. Astrometric measurements (e.g. those made by the Gaia spacecraft) provide a new way to search for GWs. The main difficulty facing such a search is the large size of the data set; Gaia observes more than one billion stars. I will discuss recent progress towards a practicable search for gravitational waves with Gaia and discuss the similarities with pulsar timing arrays.

Seminars in the past

Records of seminars held in the past.