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7:30 pm, Monday, January 23rd, 2017
Fairmont Lounge, St. John's College
2111 Lower Mall, UBC
Gravitational waves: exploring the extremes of physics and astronomy
Yanbei Chen
California Institute of Technology
Einstein's theory of gravity and spacetime predicts that a massive star,
after exhausting its nuclear fuel, will become a black hole, which
distorts space-time to produce an "event horizon", where gravity is so
strong that one can only enter but not escape. Space-time is also dynamic:
oscillating space-time distortions will move at the speed of light, as
gravitational waves. The search for gravitational waves started in the
1960s, finally succeeding in September 2015, when waves from two colliding
black holes 1.3 billion light years away were caught by the two detectors
of the Laser Interferometer Gravitational-wave Observatory. During a
pulse of 0.2 seconds, mirrors separated by 4 kms were moved by several
times 10^-18 meters, around 1000th the size of an atomic nucleus. A
second black-hole collision was detected in December, 2015. These
detections opened a new window on the universe. In the future,
gravitational-wave observations will not only allow us to better study
black holes, including their histories of formation and their detailed
structures, but will also reveal other violent processes in the universe.
To learn more please visit his
webpage.
Additional resources for this talk: slides(no available yet), video.
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