The analytic continuation to an imaginary velocity of the canonical partition function of a thermal system expressed in a moving frame has a natural implementation in the Euclidean path-integral formulation in terms of shifted boundary conditions. The Poincare' invariance underlying a relativistic theory implies a dependence of the free-energy on the compact length L_0 and the shift xi only through the combination beta=L_0(1+xi^2)^(1/2). This in turn implies that the energy and the momentum distributions of the thermal theory are related, a fact which is encoded in a set of Ward identities among the correlators of the energy-momentum tensor. The latter have interesting applications in lattice field theory: they offer novel ways to compute thermodynamic potentials, and a set of identities to renormalize non-perturbatively the energy-momentum tensor. At fixed bare parameters the shifted boundary conditions also provide a simple method to vary the temperature in much smaller steps than with the standard procedure.

Giusti, L., Meyer, H. (2014). Thermal field theories and shifted boundary conditions. In Proceedings, 31st International Symposium on Lattice Field Theory (Lattice 2013) : Mainz, Germany, July 29-August 3, 2013 (pp.214).

Thermal field theories and shifted boundary conditions

GIUSTI, LEONARDO
Primo
;
2014

Abstract

The analytic continuation to an imaginary velocity of the canonical partition function of a thermal system expressed in a moving frame has a natural implementation in the Euclidean path-integral formulation in terms of shifted boundary conditions. The Poincare' invariance underlying a relativistic theory implies a dependence of the free-energy on the compact length L_0 and the shift xi only through the combination beta=L_0(1+xi^2)^(1/2). This in turn implies that the energy and the momentum distributions of the thermal theory are related, a fact which is encoded in a set of Ward identities among the correlators of the energy-momentum tensor. The latter have interesting applications in lattice field theory: they offer novel ways to compute thermodynamic potentials, and a set of identities to renormalize non-perturbatively the energy-momentum tensor. At fixed bare parameters the shifted boundary conditions also provide a simple method to vary the temperature in much smaller steps than with the standard procedure.
slide + paper
High Energy Physics - Lattice; High Energy Physics - Lattice
English
31st International Symposium on Lattice Field Theory (Lattice 2013)
2013
Proceedings, 31st International Symposium on Lattice Field Theory (Lattice 2013) : Mainz, Germany, July 29-August 3, 2013
2014
214
http://arxiv.org/abs/1310.7818v1
none
Giusti, L., Meyer, H. (2014). Thermal field theories and shifted boundary conditions. In Proceedings, 31st International Symposium on Lattice Field Theory (Lattice 2013) : Mainz, Germany, July 29-August 3, 2013 (pp.214).
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/64578
Citazioni
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
Social impact