Self-consistent spectral functions in the 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>O</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mi>N</mml:mi><mml:mo stretchy="false">)</mml:mo></mml:math>
 model from the functional renormalization group

Strodthoff, Nils

doi:10.1103/physrevd.95.076002

Cited by 34 publications

(38 citation statements)

References 59 publications

(121 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(12). In a fully self-consistent calculation one would have to feed these back into the flow equations, recompute and iterate until convergence [42]. As in our previous studies [14,37,38] here we perform the first step in such an approach, thus neglecting the fluctuations due to the continuous contributions from the two-point functions inside the flow.…”

Section: Vector-meson Fluctuationsmentioning

confidence: 99%

See 1 more Smart Citation

Fluctuating vector mesons in analytically continued functional RG flow equations

Jung

Smekal

2019

Phys. Rev. D

View full text Add to dashboard Cite

In this work we study contributions due to vector and axial-vector meson fluctuations to their in-medium spectral functions in an effective low-energy theory inspired by the gauged linear sigma model. In particular, we show how to describe these fluctuations in the effective theory by massive (axial-)vector fields in agreement with the known structure of analogous single-particle or resonance contributions to the corresponding conserved currents. The vector and axial-vector meson spectral functions are then computed by numerically solving the analytically continued functional renormalization group (aFRG) flow equations for their retarded two-point functions at finite temperature and density in the effective theory. We identify the new contributions that arise due to the (axial-)vector meson fluctuations, and assess their influence on possible signatures of a QCD critical endpoint and the restoration of chiral symmetry in thermal dilepton spectra.

show abstract

Section: Vector-meson Fluctuationsmentioning

confidence: 99%

“…by the Euclidean mass parameters at the IR scale. In a selfconsistent solution [42] they should eventually also be determined by the resulting physical pole masses, of course, possibly smeared out for resonances.…”

Section: B Spectral Functions In the Vacuummentioning

confidence: 99%

Fluctuating vector mesons in analytically continued functional RG flow equations

Jung

Smekal

2019

Phys. Rev. D

View full text Add to dashboard Cite

show abstract

“…Recent progress in the implementation of momentum-dependent couplings has been made in [218,219,220,221] and in [222,149,223,210].…”

Section: Functional Renormalization Group and Wetterich Equationmentioning

confidence: 99%

Modeling finite-volume effects and chiral symmetry breaking in two-flavor QCD thermodynamics

Klein

2017

Physics Reports

View full text Add to dashboard Cite

Finite-volume effects in Quantum Chromodynamics (QCD) have been a subject of much theoretical interest for more than two decades. They are in particular important for the analysis and interpretation of QCD simulations on a finite, discrete space-time lattice. Most of these effects are closely related to the phenomenon of spontaneous breaking of the chiral flavor symmetry and the emergence of pions as light Goldstone bosons. These long-range fluctuations are strongly affected by putting the system into a finite box, and an analysis with different methods can be organized according to the interplay between pion mass and box size. The finite volume also affects critical behavior at the chiral phase transition in QCD. In the present review, I will be mainly concerned with modeling such finite volume effects as they affect the thermodynamics of the chiral phase transition for two quark flavors.I review recent work on the analysis of finite-volume effects which makes use of the quark-meson model for dynamical chiral symmetry breaking. To account for the effects of critical long-range fluctuations close to the phase transition, most of the calculations have been performed using non-perturbative Renormalization Group (RG) methods. I give an overview over the application of these methods to a finite volume. The method, the model and the results are put into the context of related work in random matrix theory for very small volumes, chiral perturbation theory for larger volumes, and related methods and approaches. They are applied towards the analysis of finite-volume effects in lattice QCD simulations and their interpretation, mainly in the context of the chiral phase transition for two quark flavors.

show abstract

“…One interesting alternative to such reconstructions of spectral functions from lattice data, as done for the present model in Ref. [11], is given by functional approaches such as n−PI [12] and Functional Renor-malization Group (FRG) methods [13][14][15][16][17][18][19] or Dyson-Schwinger equations (DSE) [20,21], which can be analytically continued or formulated directly in the real-frequency domain. However, such approaches necessarily require truncations of an infinite set of evolution equations or equations of motion for n-point correlation functions, and thus greatly benefit from additional insights into the structure and dynamics of excitations.…”

Section: Introductionmentioning

confidence: 99%

Spectral functions and critical dynamics of the O(4) model from classical-statistical lattice simulations

2020

View full text Add to dashboard Cite

We calculate spectral functions of the relativistic O(4) model from real-time lattice simulations in classical-statistical field theory. While in the low and high temperature phase of the model, the spectral functions of longitudinal (σ) and transverse (π) modes are well described by relativistic quasi-particle peaks, we find a highly non-trivial behavior of the spectral functions in the cross over region, where additional structures appear. Similarly, we observe a significant broadening of the quasi-particle peaks, when the amount explicit O(4) symmetry breaking is reduced. We further demonstrate that in the vicinity of the O(4) critical point, the spectral functions develop an infrared power law associated with the critical dynamics, and comment on the extraction of the dynamical critical exponent z from our simulations. ω J = 0.05 / 2 9 J = 0.05 / 2 8 J = 0.05 / 2 7 J = 0.05 / 2 6 J = 0.05 / 2 5 J = 0.05 / 2 4 J = 0.05 / 2 3 J = 0.05 / 2 2 J = 0.05 / 2 J = 0.05 0 50 100 150 200 250 300 350 400 450 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 ρ σ ω J = 0.05 / 2 9 J = 0.05 / 2 8 J = 0.05 / 2 7 J = 0.05 / 2 6 J = 0.05 / 2 5 J = 0.05 / 2 4 J = 0.05 / 2 3 J = 0.05 / 2 2 J = 0.05 / 2 J = 0.05

show abstract

Self-consistent spectral functions in the O(N) model from the functional renormalization group

Cited by 34 publications

References 59 publications

Fluctuating vector mesons in analytically continued functional RG flow equations

Fluctuating vector mesons in analytically continued functional RG flow equations

Modeling finite-volume effects and chiral symmetry breaking in two-flavor QCD thermodynamics

Spectral functions and critical dynamics of the O(4) model from classical-statistical lattice simulations

Contact Info

Product

Resources

About