Spectral representation of the shear viscosity for local scalar QFTs at finite temperature

Abstract

In local scalar quantum field theories (QFTs) at finite temperature correlation functions are known to satisfy certain non-perturbative constraints, which for two-point functions in particular implies the existence of a generalisation of the standard Källén-Lehmann representation. In this work, we use these constraints in order to derive a spectral representation for the shear viscosity arising from the thermal asymptotic states, ${\eta }_0$. As an example, we calculate ${\eta }_0$ in ${\varphi }^4$ theory, establishing its leading behaviour in the small and large coupling regimes.

arXiv comment21 pages, 3 figures; v3: additional references added as well as some minor text changes, matches published version

References in corpus (24)

• Transport coefficients in high temperature gauge theories: (II) Beyond leading log
• Transport coefficients in high temperature gauge theories: (I) Leading-log results
• A calculation of the bulk viscosity in SU(3) gluodynamics
• Hydrodynamic Transport Coefficients in Relativistic Scalar Field Theory
• A calculation of the shear viscosity in SU(3) gluodynamics
• From Quantum Field Theory to Hydrodynamics: Transport Coefficients and Effective Kinetic Theory
• Transport Coefficients of Gluon Plasma
• Transport Properties of the Quark-Gluon Plasma -- A Lattice QCD Perspective
• Spectral Functions for the Quark-Meson Model Phase Diagram from the Functional Renormalization Group
• Transport Coefficients in Yang--Mills Theory and QCD
• Real time correlation functions and the functional renormalisation group
• Temperature dependence of shear viscosity of $SU(3)$--gluodynamics within lattice simulation
• Gluon spectral functions and transport coefficients in Yang--Mills theory
• Shear Viscosity in the O(N) Model
• Computing Spectral Densities in Finite Temperature Field Theory
• Towards a Relativistic KMS Condition
• QCD Shear Viscosity at (almost) NLO
• Finite temperature spectral functions in the O(N)-model
• Flow equations for spectral functions at finite external momenta
• Spectral functions in the ${\varphi }^4$-theory from the spectral DSE
• Transport coefficients from the 2PI effective action
• Axiomatic Analyticity Properties and Representations of Particles in Thermal Quantum Field Theory
• Asymptotic dynamics of thermal quantum fields
• Fermionic excitations at finite temperature and density

Cited by in corpus (8)

• The Present and Future of QCD
• Pion spectral properties above the chiral crossover of QCD
• Chiral spin symmetry and hot/dense QCD
• Pseudo-scalar meson spectral properties in the chiral crossover region of QCD
• Euclidean thermal correlation functions in local QFT
• Real-time observables from Euclidean thermal correlation functions
• Shear viscosity from perturbative Quantum Chromodynamics to the hadron resonance gas at finite baryon, strangeness, and electric charge densities
• Non-perturbative BRST symmetry and the spectral structure of the ghost propagator