The friendship between Max Planck and Albert Einstein

There are many levels of fascination to study Planck and Einstein and their relationship. In the book I mention they're almost a bit like Felix and Oskar in The Odd Couple, because we have the very upright and proper and dignified German, Prussian gentleman in Planck, and with Albert Einstein we have someone more loosey-goosey, if you will, and passionate and impulsive and ready to be playful, perhaps, sometimes cruel. And they had incredibly different politics. Planck was absolutely dedicated to his homeland come what may, which has maybe tarnished his legacy when the Nazis took power. Einstein found nationalism absolutely revolting and he wanted a one-world government and didn't really see himself allied with any nation too much. But they were united in a great passion for searching for fundamental truth and they just loved this about one another and they played music together and these kind of more eternal ideals kept them together despite all these practical differences. In 1933 when Hitler came to power, Einstein was one of the first to stand up outside of Germany. He was in America at the time and sort of speak to this new government and the horrors of it and what was going on. And Planck and other German physicists thought, you may be right on some of the details but you're airing our dirty laundry out of turn and it's just completely inappropriate. And there was a real break in their friendship, some very poignant letters back and forth that we deal with in the book. And they never spoke again. Einstein never returned to Germany. But when Planck did pass away in 1947, Einstein then wrote on behalf of the National Academies of Science in America, he wrote a beautiful tribute to Max Planck. But that was the last of their friendship.