Planck Dies: Father of Quantum Theory Leaves Lasting Legacy
Max Planck didn't want to overturn physics. He wanted to solve a narrow technical problem: why hot objects glow the colors they do. His answer — that energy comes in discrete packets, not continuous waves — was so radical he spent years trying to walk it back. He couldn't. The quantum he invented in 1900 became the foundation of modern physics. He died in 1947 at 89, having lived long enough to see his reluctant revolution produce the atomic bomb.
October 4, 1947
79 years ago
What Else Happened on October 4
Rebels breached the walls of Chang'an, ending the short-lived Xin dynasty and the reign of Emperor Wang Mang. This violent collapse plunged China into years of …
Wang Mang's head ended up in the imperial treasury. Rebels stormed Chang'an during a peasant uprising, captured the emperor, killed him, and cut off his head. T…
Heraclius sailed from Carthage to Constantinople with a fleet and an army. Emperor Phocas had murdered his way to power eight years earlier and driven the empir…
Pope Innocent III crowned Otto IV as Holy Roman Emperor in Rome, formalizing a fragile alliance between the papacy and the Welf dynasty. This coronation briefly…
Caliph al-Adil II ruled the Abbasid Caliphate for six months. His vizier had him assassinated and replaced him with his uncle. Al-Adil was 25. The Abbasid Calip…
The Byzantine-Venetian War ended in 1302 after eight years of fighting over trade routes and Mediterranean ports. Venice kept its commercial privileges in Const…
Talk to History
Have a conversation with historical figures who witnessed this era. Ask questions, explore perspectives, and bring history to life.