General Relativity painted black holes as eternal cosmic prisons from which nothing escapes. In 1974, Stephen Hawking united quantum field theory with thermodynamics to prove they are slowly boiling away.
If the cosmos endures forever and obeys statistical mechanics, every physical configuration must repeat infinitely—giving rise to the disturbing paradox of conscious minds fluctuating spontaneously out of thermal chaos.
Every law of fundamental physics works identically backward and forward. Why, then, can you never unscramble an egg? Ludwig Boltzmann solved the mystery with a single statistical equation.