Bosonic Loop Diagrams as Perturbative Solutions of the Classical Field Equations in phi(4)-Theory

作者：Finster Felix^*; Tolksdorf Juergen

来源：Journal of Mathematical Physics, 2012, 53(5): 052305.

DOI：10.1063/1.4718333

Solutions of the classical phi(4)-theory in Minkowski space-time are analyzed in a perturbation expansion in the nonlinearity. Using the language of Feynman diagrams, the solution of the Cauchy problem is expressed in terms of tree diagrams which involve the retarded Green%26apos;s function and have one outgoing leg. In order to obtain general tree diagrams, we set up a %26quot;classical measurement process%26quot; in which a virtual observer of a scattering experiment modifies the field and detects suitable energy differences. By adding a classical stochastic background field, we even obtain all loop diagrams. The expansions are compared with the standard Feynman diagrams of the corresponding quantum field theory.

• 出版日期2012-5