Mercoledì 27 giugno 2018 ore 11:00 Scuola Normale Superiore Pisa Aula Marie Curie
Marco Cavaglià (University of Mississippi)
Terrà un seminario dal titolo:
“One wave, Two neutron stars, Three Nobel laureates, Four detectorsand Five(.9) black hole pairs: The birth of multi-messenger astrophysics”
In 1916 Albert Einstein demonstrated that the theory of general relativity allows for wave-like, space time perturbations propagating with the speed of light. However, because of the extreme weakness of gravity, their detection looked like an impossible task. Gravitational waves even became a matter of controversy with Einstein himself becoming convinced they might not exist. It took several decades before the first attempts to detect gravitational waves were made by Joseph Weber. Later, the orbital decay of the PSR B1913+16 binary pulsar provided an indirect proof of their existence, but direct detection still remained elusive. The long quest to detect gravitational waves finally ended on February 11, 2016, when scientists from the Laser Interferometer Gravitational-wave Observatory (LIGO) Scientific Collaboration and the Virgo Collaboration announced the first observation of a gravitational-wave signal from a merger of two stellar mass black holes. In the next few years, Advanced LIGO and Virgo will detect hundreds of signals from different astrophysical sources, allowing scientists to map the dark, gravitational universe. How many black holes populate the sky? How do they form and merge? How does the central engine of a gamma-ray burst work? What is the equation of state of neutron stars? Is General Relativity the correct theory of gravity in strong regimes? These are just a few of the unanswered questions that gravitational-wave astronomy will help to answer.