BCS theory is the first microscopic theory of superconductivity since its discovery in 1911. The theory describes superconductivity as a microscopic effect caused by a condensation of Cooper pairs into a boson-like state. The theory is also used in nuclear physics to describe the pairing interaction between nucleons in an atomic nucleus. It was proposed by John Bardeen, Leon Cooper, and John Robert Schrieffer ("BCS") in 1957; they received the Nobel Prize in Physics for this theory in 1972.