Max Karl Ernst Ludwig Planck, ForMemRS, (April 23, 1858 – October 4, 1947) was a German physicist who discovered quantum physics, initiating a revolution in natural science and philosophy. He is regarded as the founder of quantum theory, for which he received the Nobel Prize in Physics in 1918.
Leonard Susskind [b. 1940] is an American physicist specializing in string theory and quantum field theory. He is Felix Bloch professor of theoretical physics at Stanford. He is a notable promoter of public understanding of science, and his entire course on quantum physics can be downloaded on the iTunes platform from Stanford.