A Debate Over the Physics of Time | Quanta Magazine
Vincent Orback

Einstein once described his friend Michele Besso as "the best sounding board in Europe" for scientific ideas. They attended university together in Zurich; later they were colleagues at the patent office in Bern. When Besso died in the spring of 1955, Einstein - knowing that his own time was also running out - wrote a now-famous letter to Besso's family.