For better or worse, Nova powers as a whole are capable of darn near anything you've seen someone with superpowers do in a comic book. As a whole they're extremely broad. I know that's vague, but I'm not sure there's a better answer there.

As for Quantum, Novas have the ability to manipulate the fundamental quantum forces of the universe (gravitation, electromagnetism, weak interaction and strong interaction). When someone with the genetic potential for manipulating quantum forces falls under the right circumstance (which varies depending on the individual), a structure in their brain...