Quantum Mechanics and Determinism

In the piece that we read about neuroscience, Greene and Cohen casually mention that Quantum Mechanical Theory is not deterministic. While this fact does not pose a threat to the argument contained in the paper, as Prof. Tresan pointed out in class, it is still an immensely important discovery in the field of physics. The link below gives a thorough look at the topic. 

http://plato.stanford.edu/entries/determinism-causal/

(I know it is long, but you can skip to Section 4 for a more concise read.)