Multiplicity of self-adjoint realisations of the (2+1)-fermionic model of Ter-Martirosyan—Skornyakov type

Autor: Alessandro Michelangeli, Andrea Ottolini
Rok vydání: 2018
Předmět:
Zdroj: Reports on Mathematical Physics. 81:1-38
ISSN: 0034-4877
DOI: 10.1016/s0034-4877(18)30014-4
Popis: We reconstruct the whole family of self-adjoint Hamiltonians of Ter-Martirosyan—Skornyakov type for a system of two identical fermions coupled with a third particle of different nature through an interaction of zero range. We proceed through an operator-theoretic approach based on the self-adjoint extension theory of Krein, Visik, and Birman. We identify the explicit ‘Krein—Visik-Birman extension parameter’ as an operator on the ‘space of charges’ for this model (the ‘Krein space’) and we come to formulate a sharp conjecture on the dimensionality of its kernel. Based on our conjecture, for which we also discuss an amount of evidence, we explain the emergence of a multiplicity of extensions in a suitable regime of masses and we reproduce for the first time the previous partial constructions obtained by means of an alternative quadratic form approach.
Databáze: OpenAIRE