Friday 09 Feb 2018: [Seminar] Black holes: Einstein's gravity and rocket science!
Prof. Chris Done - Durham University
4th Floor Physics 14:30-15:30
The X-ray emission from accreting black holes in our own galaxy was key in transforming black holes from
a speculative extrapolation of Einsteins gravity into observational science. I will review how we can use this X-ray emission to test General Relativity in the strong field limit, with observational evidence for the event horizon and last stable circular orbit. More recently, we have shown that the strong, low frequency quasi-periodic oscillations seen in these systems are most likely produced by Lense-Thirring precession. This is another strong field relativistic effect associated with vertically tilted orbits around a spinning black hole. Not only does this solve the 25 year mystery of the nature of these signals, it also addresses more recent controversies over the nature and geometry of the accretion flow.