Today is the birthday of Enrico Fermi, born in 1901, he opened the atomic age by working out the mathematics of the neutron. He immigrated to the United States from Italy during the Hitler years and built the first atomic reactor. When he received the Nobel Prize, he wouldn’t wear the fascist uniform or give the salute. He discovered that thermal neutrons, those that are slowed down are more effective in a controlled chain reaction. He died of cancer at age 53.