The Intricacies of Emergent Gravity

Nothing escapes a black hole… or does it? In the 1970s, Stephen Hawking described a subtle process by which black holes can “evaporate,” with some particles evading gravitational oblivion. This phenomenon, now dubbed “Hawking radiation,” seems inherently at odds with general relativity, but it gets weirder still: If particles can escape, do they preserve some information about the matter that was obliterated? Leonard Susskind, a physicist at Stanford University, found himself at odds with Hawking when it came to answering this question. In this episode, co-host Janna Levin speaks with Susskind about the “black hole war” that ensued and the powerful scientific lessons that have radiated from one of the most famous paradoxes in physics.