- Speaker: Prof. Unruh, William (University of British Columbia, USA)
- Date: Friday July 4, 2014 11:00
Hawking's predictions that black holes should radiate was one of the most
surprizing result of late 20th century physics.Unfortunately, finding small
black holes whose radiation would be measureable seems impossible. In 1981 I showed that there are analog systems, systems with horizons to the travelling
of other kinds of waves (sound, light, surface waves,...) where the
predictions of Hawking should also follow-- those systems should also emit
quantum noise with a thermal spectrum. I will describe and experiment we
carried out in which that thermal spectrum was measured for surface waves on
flowing water. While the qunatum noise itself was unmeasureable, the
stimulated emission ( which Einstein showed was closely related to the
spontaneous emission) was measureable, and showed tha the quantum noise has a
thermal spectrum. This talk illustrates the amazing feature of physics to
reveal close ties between areas one would never have suspected were related.