Published December 4, 2009
| Version v1
Journal article
Many-Body Green Function of Degenerate Systems
- 1. Institut de Mineralogie et de Physique des Milieux Condenses, CNRS UMR 7590, Universites Paris 6 et 7, IPGP, 140 rue de Lourmel, 75015 Paris (France)
- 2. Dipartimento di Matematica, Universita di Roma La Sapienza, Roma (Italy)
- 3. Universite Paris Est, CERMICS, Projet MICMAC ENPC-INRIA, 6 and 8 Avenue Pascal, 77455 Marne-la-Vallee Cedex 2 (France)
Description
A rigorous nonperturbative adiabatic approximation of the evolution operator in the many-body physics of degenerate systems is derived. This approximation is used to solve the long-standing problem of the choice of the initial states of H0 leading to eigenstates of H0+V for degenerate systems. These initial states are eigenstates of P0VP0, where P0 is the projection onto a degenerate eigenspace of H0. This result is used to give the proper definition of the Green function, the statistical Green function and the nonequilibrium Green function of degenerate systems. The convergence of these Green functions is established.
Additional details
Identifiers
- DOI
- 10.1103/PhysRevLett.103.230401;
- arXiv
- arXiv:0906.2052v2;
Publishing Information
- Journal Title
- Physical Review Letters
- Journal Volume
- 103
- Journal Issue
- 23
- Journal Page Range
- p. 230401-230401.4
- ISSN
- 0031-9007
- CODEN
- PRLTAO
INIS
- Country of Publication
- United States
- Country of Input or Organization
- International Atomic Energy Agency (IAEA)
- INIS RN
- 41101327
- Subject category
- S97: MATHEMATICAL METHODS AND COMPUTING;
- Descriptors DEI
- ADIABATIC APPROXIMATION; CONVERGENCE; EIGENSTATES; GREEN FUNCTION; MANY-BODY PROBLEM; MATHEMATICAL EVOLUTION
- Descriptors DEC
- APPROXIMATIONS; CALCULATION METHODS; EVOLUTION; FUNCTIONS
Optional Information
- Notes
- (c) 2009 The American Physical Society