Professor Stephen Hawking's groundbreaking work earned him dozens of accolades over his lifetime, but the coveted Nobel Prize always eluded him.

His discovery in 1974 that black holes should emit radiation was initially controversial as it was widely accepted that nothing, not even light, could escape their gravity.

His theory, dubbed "Hawking Radiation", was based on mathematical concepts arising from quantum mechanics, the branch of science dealing with sub-atomic particles. It stated that this emission of radiation eventually causes black holes to "evaporate" and vanish.

Although it became widely accepted, Hawking Radiation was never proved by astronomers or physicists - if it had, it would almost certainly have earned him the Nobel Prize.

In January 2016, Prof Hawking gave a Reith Lecture broadcast on the BBC in which he joked that his lack of a Nobel Prize was "a pity".