An Analogy Between Time-Dependent Diffusion Theory and Classical Mechanics

An analogy is set up between a theory of time-dependent neutron diffusion and the Lagrange theory of mechanical systems, by observing the similarity between Hamilton's Principle and a well-known variational principle in diffusion theory. Recognition of the redundancy of certain variables makes it possible to proceed correctly to an equivalent Hamiltonian theory and the analog of the canonical integral principle is then shown to be a modification of the original variational principle which permits the use of trial functions that have discontinuous time behavior.