What experiments did Einstien perform to discover and prove the photoelectric effect?
Einstein was known for a mathematical explanation for why it occurred. He did perform thought experiments. (an attempt to conceive the consequences of an intervention in the world without actually intervening. In some cases, an actual experiment would be preferable but is impossible in practice or perhaps even in theory.~http://www.filosofia.net/materiales/rec/glosaen.htm) but these don’t generally lead to observable results. You can find more information about the Photoelectric effect and the differing experiments on wikipedia: http://en.wikipedia.
