Saturday Night Science: Planck

Theoretical physics is usually a young person’s game. Many of the greatest breakthroughs have been made by researchers in their twenties, just having mastered existing theories while remaining intellectually flexible and open to new ideas. Max Planck, born in 1858, was an exception to this rule. He spent most of his twenties living with his parents and despairing of finding a paid position in academia. He was 36 when he took on the project of understanding heat radiation, and 42 when he explained it in terms which would launch the quantum revolution in physics. He was in his fifties when he discovered the zero-point energy of the vacuum, and remained engaged and active in science until shortly before his death in 1947 at the age of 89. As theoretical physics editor for the then most prestigious physics journal in the world, Annalen der Physik, in 1905 he approved publication of Einstein’s special theory of relativity, embraced the new ideas from a young outsider with neither a Ph.D. nor an academic position, extended the theory in his own work in subsequent years, and was instrumental in persuading Einstein to come to Berlin, where he became a close friend.