English

Truncation errors in self-similar continuous unitary transformations

Strongly Correlated Electrons 2011-04-14 v1 Quantum Physics

Abstract

Effects of truncation in self-similar continuous unitary transformations (S-CUT) are estimated rigorously. We find a formal description via an inhomogeneous flow equation. In this way, we are able to quantify truncation errors within the framework of the S-CUT and obtain rigorous error bounds for the ground state energy and the highest excited level. These bounds can be lowered exploiting symmetries of the Hamiltonian. We illustrate our approach with results for a toy model of two interacting hard-core bosons and the dimerized S=1/2 Heisenberg chain.

Keywords

Cite

@article{arxiv.1009.3744,
  title  = {Truncation errors in self-similar continuous unitary transformations},
  author = {Nils A. Drescher and Tim Fischer and Götz S. Uhrig},
  journal= {arXiv preprint arXiv:1009.3744},
  year   = {2011}
}

Comments

17 pages, 8 figures

R2 v1 2026-06-21T16:16:05.010Z