Career & the Cambridge Years

Stephen Hawking spent essentially his entire working life at the University of Cambridge, much of it at the Department of Applied Mathematics and Theoretical Physics. Over more than forty years he rose from a doctoral student who had been told he had no future to the holder of one of the most storied chairs in science, and produced the run of discoveries that made his name.

A research career begins

Hawking completed his PhD under Dennis Sciama in 1965. His thesis already showed the direction of his thinking: it dealt with the properties of an expanding universe and the question of singularities, the points where the equations of general relativity break down. He had been galvanised by the work of the mathematician Roger Penrose, who had shown that singularities could form in collapsing stars.

The collaboration with Penrose became one of the most productive in twentieth-century physics. Through the late 1960s the two of them developed the singularity theorems, proving that, under general relativity, both black holes and the universe itself must contain singularities. It was rigorous, original work, and it established Hawking, still in his twenties, as a serious figure.

The great discoveries

The 1970s were Hawking's most productive decade. In 1971 he proved his area theorem, that the surface area of a black hole's event horizon can never decrease, a result that hinted at a deep and unexpected link between black holes and the physics of heat. Then, in 1974, came the discovery that carries his name: Hawking radiation, the prediction that black holes are not entirely black but slowly emit radiation and can eventually evaporate. It united, for the first time in a single result, gravity, quantum mechanics and thermodynamics, and it remains his most celebrated contribution.

Recognition followed quickly. In 1974, at the age of thirty-two, he was elected a Fellow of the Royal Society, unusually young for the honour.

The Lucasian Chair

In 1979 Hawking was appointed Lucasian Professor of Mathematics at Cambridge. The position is among the most prestigious in the academic world; its holders have included Isaac Newton and Paul Dirac. Hawking held the chair for thirty years, until reaching the customary retirement point in 2009, after which he continued as Director of Research at the department. To occupy Newton's chair, while doing original physics from a wheelchair and, after 1985, through a speech synthesiser, made him a singular figure in the public imagination as well as the scientific one.

Around him grew a research group of students and collaborators. Working with him was demanding in unusual ways, the slow, deliberate pace of his communication forcing a particular clarity, but a long line of physicists trained under him went on to distinguished careers of their own.

Fame, and work that never stopped

In 1988 Hawking published A Brief History of Time, his attempt to explain the universe to a general readership. Its astonishing success, tens of millions of copies sold, transformed him from a respected physicist into a global celebrity, a story told on the books pages.

Fame did not slow the physics. He continued to work on the deepest problems in the field for decades, returning again and again to the black hole information paradox that his own discovery had created, contributing to the theory of cosmic inflation and the origin of the universe, and publishing scientific papers into the final years of his life. He also threw himself into public engagement, lectures, television, and advocacy on issues from disability rights to the future of humanity.

By the time he stepped back from the Lucasian Chair in 2009, Hawking had spent half a century at the frontier of theoretical physics, defying both the disease that should have stopped him and the limits of what anyone expected a single career to contain.

In taking the Lucasian Chair he followed Isaac Newton; the two are compared in Hawking vs Newton.

His 1966 doctoral work is covered in Stephen Hawking's PhD thesis.