Science

...credibility in my mind. He was being stupid about plutonium, and is still, from what I understand, stupid about nuclear technology in general. Kaku does have a cool haircut though.

A flaw in the film by the way is that it depicts Margarethe Bohr using the word plutonium in 1941 which is impossible, since the existence of plutonium was not known in 1941 in Denmark - it had only been identified on an atomic scale in early 1942 from experiments conducting in 1941 - and had definitely not been formally named by Seaborg. The code word for its existence was "49" a rather uninspiring and easily decipherable choice for element 94.

She certainly would not have known it was fissionable, nor would she understand that a reactor was required to make it, nor that it was a key to making a certain type of nuclear weapon.

Years ago, when I was at the Smithsonian, the original sample of plutonium (a few atoms on a metal target) was on display in the Museum of Science. I have no idea if it's still there.