Black holes were once thought to be perfect cosmic prisons, but Stephen Hawking's math showed they slowly leak energy and eventually evaporate. This episode traces how that idea emerged: Jacob Bekenstein's 1972 claim that black holes carry entropy proportional to their surface area, Hawking's attempt to disprove it, his 1973 Moscow meeting with Zeldovich and Starobinsky, and the equations that ended up proving his rival right. From there the hosts walk through virtual particle pairs split at the event horizon, the Unruh effect for accelerating observers, and why the black hole itself pays the energy bill by losing mass.

The conversation then follows the strange consequences: temperature rising as mass falls, evaporation timescales around 10 to the 67th years for stellar-mass black holes, and why today's black holes are colder than the 2.7 K ...