As usual for a Christopher Nolan movie, "Oppenheimer" is very long, very loud, very overblown and very shallow. It could have been subtitled "Theoretical Physics for Dummies," but the main dummy is Nolan, whose "art" consists of smearing overdone music over every scene, whether needed or not, and turning a fascinating and vital story into hamfisted, often risible drama. Its three hours seemed like six.