2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/187111We look at a real scalar field in thermal equilibrium in the context of the new normal ordering and field split defined by Evans and Steer. We show that the field split defines a natural canonical transformation, but that this transformation differs from others known in thermal field theory.13 pages, LaTeX. (Revisions made to discussion and various small errors in equations corrected)High Energy Physics - Phenomenologytext