Density Formalism for Quantum Theory

Paul S. Hubbard

Nuclear magnetic relaxation phenomena are studied by means of a density operator formalism. Both quantum mechanical and semiclassical forms of a density operator relaxation theory are developed using this formalism. Both forms of the theory are applicable when the spin energy depends explicity on time, and both predict correctly the observed density operator. The relaxation of a system of identical spin-1/2 nuclei is calculated as an example. (T.F.H.)

Andrei Yu. Khrennikov

Long, Gui Lu

We give the mathematical theory of duality computer in the density matrix formalism. This result complements the mathematical theory of duality computer of Gudder in the pure state formalism.

Roderick I. Sutherland

A simple mathematical extension of quantum theory is presented. As well as opening the possibility of alternative methods of calculation, the additional formalism implies a new physical interpretation of the standard theory by providing a picture of an external reality. The new formalism, developed first for the single-particle case, has the advantage of generalizing immediately to quantum field theory and to the description of relativistic phenomena such as particle creation and annihilation.

Steven M. Moore