Work

Computing general observables in lattice models with complex actions

Year: 2019

Type: preprint

Abstract: The study of QFTs at finite density is hindered by the presence of the so-called sign problem. The action definition of such systems is, in fact, complex-valued making standard importance sampling Monte Carlo methods ineffective. In this work, we shall review the generalized density of states method for complex action systems and the Linear Logarithmic Relaxation algorithm (LLR). We will focus on the recent developments regarding the bias control of the LLR method and the evaluation of general observables in the DoS+LLR framework. Recent results on the well-known relativistic Bose gas will be presented, proving that in our approach the phase factor can be consistently evaluated over hundreds of orders of magnitude. A first exploratory study on the Thirring model in the DoS formalism will be presented as well.

Source: arXiv (Cornell University)

DOI: 10.48550/arxiv.1912.04190

Authors: Francesconi, Olmo, Holzmann, Markus, Lucini, Biagio, Rago, Antonio, Rantaharju, Jarno

Institutions: Centre National de la Recherche Scientifique, Laboratoire de Physique et Modélisation des Milieux Condensés, Swansea University, University of Plymouth, Helsinki Institute of Physics

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Fondation Nanosciences, European Commission, Agence Nationale de la Recherche, Science and Technology Facilities Council

Awards: G2121614283, G2243907913, G292453335, G4702408450, European network for Particle physics, Lattice field theory and Extreme computing, Fields, Strings and Lattices: From the Inflationary Universe to High-Energy Colliders, G7235258663, G8964069747, Fields, Strings and Lattices: From the Inflationary Universe to High-Energy Colliders, G994248709

OpenAlex ID: W4313285290

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