Albert Einstein

Albert Einstein spent his honeymoon in 1903 working on physics problems with his new wife Mileva Marić, a brilliant mathematician who had scored higher than him in several university courses. She wasn't just helping — contemporary letters suggest she was deriving key equations for what would become special relativity. Yet when the papers were published, only Albert's name appeared.

But Einstein's domestic arrangements grew even more peculiar. After divorcing Mileva in 1919, he married his cousin Elsa — then promptly began a decades-long affair with Elsa's daughter from her first marriage. When that relationship cooled, Einstein kept a little black book of women he called his "board of directors," rotating through affairs while Elsa pretended not to notice. His secretary later revealed he received love letters from admirers worldwide, many of which he answered personally.

The man who unlocked the secrets of space and time was utterly baffled by human relationships. He once wrote to a friend that marriage was "an attempt to make something lasting out of an incident." When Elsa died in 1936, Einstein refused to remarry, declaring himself "not suited for close relationships." Instead, he lived his final decades in Princeton with his stepdaughter Margot, his secretary Helen Dukas, and a succession of cats — including one that suffered from depression, which Einstein tried to cure by telling it philosophical jokes.

Einstein died in 1955, but not before removing his own brain during the autopsy wasn't authorized. The pathologist, Dr. Thomas Harvey, simply took it home in a jar, keeping it in his basement for decades and occasionally mailing pieces to researchers. Einstein's final wish was to be cremated with no grave marker — he feared becoming a site of pilgrimage. His brain had other plans.