Finite-representation approximation of lattice gauge theories at the continuum limit with tensor networks

Autor(en)

Boye Buyens, Simone Montangero, Jutho Haegeman, Frank Verstraete, Karel Van Acoleyen

Abstrakt

It has been established that matrix product states can be used to compute the ground state and single-particle excitations and their properties of lattice gauge theories at the continuum limit. However, by construction, in this formalism the Hilbert space of the gauge fields is truncated to a finite number of irreducible representations of the gauge group. We investigate quantitatively the influence of the truncation of the infinite number of representations in the Schwinger model, one-flavor QED 2, with a uniform electric background field. We compute the two-site reduced density matrix of the ground state and the weight of each of the representations. We find that this weight decays exponentially with the quadratic Casimir invariant of the representation which justifies the approach of truncating the Hilbert space of the gauge fields. Finally, we compute the single-particle spectrum of the model as a function of the electric background field.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Ghent University , Universität Ulm, Universität des Saarlandes

Journal

Physical Review D

Band

95

Anzahl der Seiten

23

ISSN

1550-7998

DOI

https://doi.org/10.1103/PhysRevD.95.094509

Publikationsdatum

05-2017

Peer-reviewed

Ja

ÖFOS 2012

103025 Quantenmechanik, 103012 Hochenergiephysik

Schlagwörter

ASJC Scopus Sachgebiete

Nuclear and High Energy Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a29249c6-7450-474c-a4a2-b434c2d269a2