Variational wave functional in quantum field theory

Tiktopoulos, G

dc.contributor.author	Tiktopoulos, G	en
dc.date.accessioned	2014-03-01T01:14:16Z
dc.date.available	2014-03-01T01:14:16Z
dc.date.issued	1998	en
dc.identifier.issn	0556-2821	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12963
dc.subject	Effective Potential	en
dc.subject	Higher Dimensions	en
dc.subject	Numerical Approximation	en
dc.subject	Quantum Field Theory	en
dc.subject	Scalar Field	en
dc.subject	Ultraviolet	en
dc.subject	Variational Principle	en
dc.subject.classification	Astronomy & Astrophysics	en
dc.subject.classification	Physics, Particles & Fields	en
dc.subject.other	OPTIMIZED DELTA-EXPANSION	en
dc.subject.other	GROSS-NEVEU MODEL	en
dc.subject.other	ANHARMONIC-OSCILLATOR	en
dc.subject.other	PERTURBATION-THEORY	en
dc.subject.other	LAMBDA-PHI-4 THEORY	en
dc.subject.other	SYMMETRY BREAKING	en
dc.subject.other	SERIES	en
dc.subject.other	RENORMALIZATION	en
dc.title	Variational wave functional in quantum field theory	en
heal.type	journalArticle	en
heal.identifier.primary	10.1103/PhysRevD.57.6429	en
heal.identifier.secondary	http://dx.doi.org/10.1103/PhysRevD.57.6429	en
heal.language	English	en
heal.publicationDate	1998	en
heal.abstract	Variational (Rayleigh-Ritz) methods are applied to local quantum field theory. For scalar theories the wave functional is parametrized in the form of a superposition of Gaussians and the expectation value of the Hamiltonian is expressed in a form that can be minimized numerically. A scheme of successive refinements of the superposition is proposed that may converge to the exact functional. As an illustration, a simple numerical approximation for the effective potential is worked out based on minimization with respect to five variational parameters. A variational principle is formulated for the fermion vacuum energy as a functional of the scalar fields to which the fermions are coupled. The discussion in this paper is given for scalar and fermion interactions in 1+1 dimensions. The extension to higher dimensions encounters a more involved structure of ultraviolet divergences and is deferred to future work.	en
heal.publisher	AMERICAN PHYSICAL SOC	en
heal.journalName	Physical Review D - Particles, Fields, Gravitation and Cosmology	en
dc.identifier.doi	10.1103/PhysRevD.57.6429	en
dc.identifier.isi	ISI:000073767400052	en
dc.identifier.volume	57	en
dc.identifier.issue	10	en
dc.identifier.spage	6429	en
dc.identifier.epage	6440	en