Paul Davies
Paul Charles William Davies, AM (born 22 April 1946) is an English physicist, writer and broadcaster. Davies\' inquiries have included theoretical physics, cosmology, and astrobiology; his research has been mainly in the area of quantum field theory in curved spacetime. Notable contributions are the so-called Fulling–Davies–Unruh effect, according to which an observer accelerating through empty space will perceive a bath of thermal radiation, and the Bunch–Davies vacuum state, often used as the basis for explaining the fluctuations in the cosmic background radiation left over from the big bang. A paper co-authored with Stephen Fulling and William Unruh was the first to suggest that black holes evaporating via the Hawking effect lose mass as a result of a flux of negative energy streaming into the hole from the surrounding space. Davies has had a longstanding association with the problem of time’s arrow, and was also a forerunner of the theory that life on Earth may have come from Mars cocooned in rocks ejected by asteroid and comet impacts. During his time in Australia he helped establish the Australian Centre for Astrobiology. Davies was an author on the widely criticized Science article \"A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus.\"