TITLE,AUTHOR,PUBLICATION DATE,UNIQUE NUMBER,DOI,REPORT NUMBER(s),OTHER NUMBER(s),CONTRACT NUMBER,RESEARCH ORG.,SPONSORING ORG.,SUBJECT,KEYWORDS,RELATED WEB PAGES,ABSTRACT
"The Theory of Quantized Fields. III","Schwinger, J.","May 1953",ACC0112,,NP-4565,OSTI ID: 4368814,6N-onr-24806,"Harvard University, Cambridge, Mass.","US Atomic Energy Commission (AEC)","Field Theory","Physics; Currents; Eigenfunctions; Eigenvalues; Electrodynamics; Electromagnetic Fields; Energy; Field Theory; Mathematics; Momentum; Photons; Quantum Electrodynamics; Quantum Mechanics","Julian Schwinger and the Source Theory (http://www.osti.gov/accomplishments/schwinger.html)","In this paper we discuss the electromagnetic field, as perturbed by a prescribed current. All quantities of physical interest in various situations, eigenvalues, eigenfunctions, and transformation probabilities, are derived from a general transformation function which is expressed in a non-Hermitian representation. The problems treated are: the determination of the energy-momentum eigenvalues and eigenfunctions for the isolated electromagnetic field, and the energy eigenvalues and eigenfunctions for the field perturbed by a time-independent current that departs from zero only within a finite time interval, and for a time-dependent current that assumes non-vanishing time-independent values initially and finally. The results are applied in a discussion of the intra-red catastrophe and of the adiabatic theorem. It is shown how the latter can be exploited to give a uniform formulation for all problems requiring the evaluation of transition probabilities or eigenvalue displacements.",