Eur. Phys. J. Special Topics 227, 2281–2287 (2019)
https://doi.org/10.1140/epjst/e2018-800058-3

Regular Article

Towards verified numerical renormalization group calculations

Lehrstuhl für Theoretische Physik I, Physikalisches Institut, Am Hubland Universität Würzburg, 97074 Würzburg, Germany

^a e-mail: Peter.Schmitteckert@physik.uni-wuerzburg.de

Received: 15 April 2018
Received in final form: 11 June 2018
Published online: 24 January 2019

Abstract

Numerical approaches are an important tool to study strongly correlated quantum systems. However, their fragility with respect to rounding errors is not well studied and numerically verified enclosures of the results are not available. In this work, we apply interval arithmetic to the well established numerical renormalization group scheme. This extension enables us to provide a numerically verified NRG excitation spectrum.