Werner Karl Heisenberg, a German physicist, Nobel laureate, and father of uncertainty principle (it is impossible to know exactly the momentum and location of a particle at the same time). Niels Bohr, a Danish physicist, Nobel laureate and father of complementarity (photon can be regarded as a particle and also wave). Between the World War I and II, the two shared a real mentor/protégé relationship. With the start of the World War II, Heisenberg stayed on in Germany to lead their atomic energy for peaceful purposes (possibly the atomic bomb), while Bohr in German-occupied-Denmark worked under severe restrictions. During the war, in 1941, Heisenberg and Bohr met on evening in Copenhagen. Post that meeting the relationship was irreparably broken. What transpired between the two during that evening has remained speculation for the longest time.

This play, by Michael Frayn, deals with why Heisenberg visited Bohr? What did Heisenberg say to Bohr and what was Bohr answer to create an irreparable rift between the two? Was Heisenberg there to gloat of his work? his countries achievements? to fish for allies nuclear programme?  It uses the two principles (uncertainty and complementarity) very effectively in the three characters in the play; Bohr, his wife and Heisenberg as it replays the drafts of what may have transpired.

I loved it. I have heard that the movie is considerably shortened from the play. I cannot wait to either see or read the play.