Dennis Sciama

Dennis Sciama, who lived from 1926 to 1999, was a British physicist and one of the most influential mentors in the history of cosmology. He was Stephen Hawking's doctoral supervisor at Cambridge, and his guidance came at the most critical moment of Hawking's life.

His own work and influence

Sciama worked across cosmology and astrophysics, including early ideas about the origin of inertia. But his greatest legacy is arguably as a teacher. He supervised an extraordinary roster of students who went on to shape the field, including the Astronomer Royal Martin Rees, the cosmologist George Ellis, and Brandon Carter, as well as Hawking. Famously open-minded, Sciama had favoured the rival steady-state model of the universe but accepted the Big Bang when the evidence turned against his preference, a model of scientific honesty he passed on to his students.

His connection to Hawking

Sciama took Hawking on as a research student in the early 1960s, just as the diagnosis of motor neurone disease threatened to end his career before it began. Sciama's encouragement and belief helped keep him in physics through that desperate period. He pointed Hawking toward the problems that would make his name, kept him connected to the leading questions of the day, and introduced him to the wider community of relativists, including Roger Penrose, whose work would prove so important. Without Sciama's mentorship at that fragile early stage, the career that followed might never have happened.

Sciama's place in Hawking's academic family is set out in students and academic lineage.