Abstract
It has long been known that reduced density matrices (RDM) can be used to obtain the exact ground state energy of many-particle Hamiltonians by performing a constrained minimization over the set of all -representable reduced density matrices. In this paper, we present a set of -representability constraints for both bosons and fermions based on expectation values. These expectation value constraints are derived from a simple yet nontrivial recursive formula, and can easily be included in RDM-based variational schemes. The expectation value constraints are shown to provide additional -representability information when compared to existing -representability constraints.
- Received 17 April 2006
DOI:https://doi.org/10.1103/PhysRevA.74.022507
©2006 American Physical Society