As a physicist myself(although out of my field for almost 29 years now) I found the movie excellent; it excited my old passion for particle physics. I enjoyed hearing all the great names I knew from my studies, as well as my time at Fermilab doing my research for my PhD. The greats such as Einstein, Bohr, Bonn, Fermi, and Lawrence to name some.
I loved all the discussions among these brilliant men and in particular the math done on the chalk board. In. Addition, bringing in the psychological aspects that building such a weapon of mass destruction can have on the individual was another good eye opener that is usually glossed over because of politics. Even in grad school it was only mentioned rarely and left for more theoretical and philosophical departments to discuss.
All in all a good historical film as long as you can follow the back and forth time jumps. Which I believe were necessary for the full effect.