Ian Sample meets the Italian physicist Carlo Rovelli to find out about his cutting-edge research into white holes. A white hole is essentially a time-reversed black hole: a region of spacetime where matter spontaneously appears and explodes outwards. At the moment they are hypothetical objects, so Rovelli explains why he thinks they are worth exploring and reveals how they could explain one of the greatest mysteries of physics
More Stories
What 40 years as Observer science editor has taught Robin McKie – podcast
Katy Perry and Blue Origin crew return safely to Earth after space flight – video
Did you solve it? That’s numberwang!