LONDON (Reuters) - Roger Penrose, who won the 2020 Nobel Prize for Physics, said on Tuesday that the biggest outstanding riddle about black holes was the question of what went on in the very centre of them - the singularity, where density and gravity become infinite.

Penrose, professor at the University of Oxford, won half the prize of 10 million Swedish crowns ($1.1 million) for his work using mathematics to prove that black holes are a direct consequence of Albert Einstein’s general theory of relativity.

Asked by Reuters about the biggest riddle about black holes, he said: “The greatest puzzle is the singularities, because we don’t know what to do with them: You see the black holes shield us from the from the singularities.”

“As the matter collapses into the middle, the densities get larger and larger and they just exceed everything you can think of,” he said. “And we haven’t the faintest idea how to describe the physics that goes on in the middle because the densities and temperatures and goodness-knows-what are just out of all range.”

He said that if humanity wanted to understand the laws of physics in a deeper way, we would need to understand what goes on with singularities.

Penrose said he had to get out of the shower to hear the news of his prize.

“It was an extreme honour and great pleasure to hear the news this morning in a slightly unusual way - I had to get out of my shower to hear it,” Penrose told reporters.