The Bethe-Salpeter equation with fermions

Autor:	G. V. Efimov
Rok vydání:	2007
Předmět:	Coupling constant Physics Bethe–Salpeter equation Kernel (set theory) Quantum mechanics Operator (physics) Propagator Fermion Integral equation Scalar field Atomic and Molecular Physics and Optics
Zdroj:	Few-Body Systems. 41:157-184
ISSN:	1432-5411 0177-7963
DOI:	10.1007/s00601-007-0180-8
Popis:	The Bethe-Salpeter (BS) equation in the ladder approximation is studied within a fermion theory: two fermion fields (constituents) with mass m interacting via an exchange of a scalar field with mass μ. The BS equation can be written in the form of an integral equation in the configuration Euclidean x-space with the symmetric kernel K for which Tr K 2 = ∞ due to the singular character of the fermion propagator. This kernel is represented in the form K = K 0 + K I . The operator K 0 with Tr K 0 2 = ∞ is of the “fall at the center” potential type and describes a continuous spectrum only. Besides the presence of this operator leads to a restriction on the value of the coupling constant. The kernel K I with Tr K I 2 < ∞ is responsible for bound fermion-fermion states.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::2e1d7074e8c6ee7d10ddae59b343fafd https://doi.org/10.1007/s00601-007-0180-8 Zobrazit plný text záznamu Plný text ve formátu PDF