What’s he trying to say?
|Keith Brueckner helped invent special techniques for solving quantum mechanics problems.|
Schrieffer is dropping into the technical language of physics, the only way he can describe what the theorists were trying to do. But we don’t need to understand every word* to get a feeling for how the work was going. As Schrieffer tells it, he and Cooper were trying to simplify their problem. They were looking for some little piece of the physics that they could hope to take aside and solve. With the powerful mathematical tools they had learned, couldn’t they at least work out what happens between a single pair of electrons, among the countless electrons in a superconductor?
*(In case you were wondering the “Brueckner theory” and “second quantization” are techniques for dealing with the hairy mathematical problems that arise in quantum theory when you try to deal with a bunch of electrons, the “Hamiltonian” is a particular mathematical way of describing energy, which can display all the forces that influence an electron, and a “wave function” is another way of capturing all the main physics in a single equation.)