Note on the correlation energy of a many-fermion system

Christian Hainzl, Marcello Porta, Felix Rexze

Brian R. Judd

1 Basic properties.- 1.1 Reduced Density Matrices.- 1.2 N-representability.- 1.3 Norbs, Nags and Least Squares.- 1.4 Fock Space.- 1.5 Reduced Density Matrices on Fock Space.- 1.6 Unitary Invariance.- 1.7 Notes.- 1.8 Exercises.- 2 N-Representability.- 2.1 The p-rank of a State.- 2.2 Convexity.- 2.3 Ensemble N-representability.- 2.4 A Family of Convex Surfaces.- 2.5 Parameterizing.- 2.6 The Total Energy.- 2.7 The One-matrix.- 2.8 Notes.- 2.9 Exercises.- 2.10 Appendix - Figures for Chapter 2.- 3 Correlation.- 3.1 Sasaki's Formula.- 3.2 Bounds on for fermions.- 3.3 Necessary Conditions.- 3.4 A Universal Fermion Model.- 3.5 Strong Orthogonality.- 3.6 Unitary Decomposition.- 3.7 Reduced Hamiltonian Orbitals.- 3.7.1 For LiH.- 3.7.2 For H2O.- 3.8 Intracules, extracules and Statistics.- 3.9 Notes for Chapter 3.- 3.10 Exercises for Chapter 3.- 3.11 Appendix - The Pfaffian.- 4 Generalized AGP.- 4.1 Canonical form for g(12).- 4.2 Properties of GAGP.- 4.3 Extreme AGP.- 4.4 Scope of GAGP.- 4.5 Error Control.- 4.6 The GAGP Energy.- 4.7 Critical values of E.- 4.8 Hartree-Fock-Bogolubov Equations.- 4.9 Notes.- 4.10 Exercises.- 5 Boson Systems.- 5.1 Yang's Paper.- 5.2 Order Indices.- 5.3 Green's Functions and Propagators.- 5.4 Bose Condensation.- 5.5 Mesoscopic Condensation.- 5.6 Bose Liquid.- 5.7 Collective Excitations.- 5.8 Notes.- 6 Fermion Systems.- 6.1 The Superconducting Transition.- 6.2 Heterophase Superconductor.- 6.3 Notes.- 6.4 Figures.- 7 Coulson's Challenge.- 7.1 The Reduced Hamiltonian.- 7.2 Pairon Distribution function.- 7.3 Facing the Challenge!.- 7.4 Notes.

Vladimir Z. Kresin

Ming Shaw, Fu-sui Liu

Using Abrikosov's pseudo-fermion representation of a single spin and Larsen's note with pseudo-fermion energy , we describe a procedure which allows calculation of spin-spin correlation as well as spin-electron (hole) correlation using standard methods including the linked cluster theorem of diagrammatic perturbation theory.

Piotr Sitko, Lucjan Jacak

Heinz J. Schulz

Lecture notes from the Jerusalem Winter School on Theoretical Physics "Correlated Electron Systems", Dec. 1991 -- Jan. 1992. Contains a review of recent and not so recent results in the theory of correlated fermions in one dimension.