Events in Physics
Alberto Vecchio, Birmingham
OPENING A NEW OBSERVATIONAL WINDOW ON THE UNIVERSE WITH GRAVITATIONAL WAVES
Einstein's theory of general relativity predicts that the motion of mass produces "ripples" of spacetime (gravitational waves) that propagate at the speed of light. Gravitational radiation is generated abundantly by compact objects, such as neutron stars and black holes. Studying this new form of radiation will convey rich and novel information about a variety of astrophysical processes, cosmology and fundamental physics.
A world-wide network of km-scale ground-based gravitational wave laser interferometers are currently in operation at unprecedented sensitivity. They include LIGO in the USA, the British/German GEO-600 and the French-Italian VIRGO. The instruments have just completed a 2-year long science run and are now undergoing incremental upgrades interleaved by observational campaigns. In parallel, ESA and NASA are actively pursuing the Laser Interferometer Space Antenna, a 5-million km-arm gravitational wave instrument. I will review the current status of searches for gravitational waves, present direct observational limits on selected classes of sources and discuss some of the challenges ahead.