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Related papers: Universality of the Nf=2 Running Coupling

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We propose a new method to compute the running coupling constant of gauge theories on the lattice. We first give the definition of the running coupling in the new scheme using the Wilson loops in a finite volume, and explain how the running…

We study the perturbative behavior of the Yang-Mills gradient flow in the Schr\"odinger Functional, both in the continuum and on the lattice. The energy density of the flow field is used to define a running coupling at a scale given by the…

High Energy Physics - Lattice · Physics 2013-10-10 Patrick Fritzsch , Alberto Ramos

We compute the Schroedinger functional (SF) for the case of lattice QCD with Wilson fermions (with and without SW improvement) at two-loop order in lattice perturbation theory. This allows us to extract the three-loop beta-function in the…

High Energy Physics - Lattice · Physics 2008-11-26 Achim Bode , Peter Weisz , Ulli Wolff

We discuss how to define and obtain the running coupling of a gauge theory in the approach of the Schwinger-Dyson equation, in order to perform a non-perturbative study of the theory. For this purpose, we introduce the nonlocally…

High Energy Physics - Phenomenology · Physics 2009-08-11 Kei-Ichi Kondo

I examine some properties of the overlap operator in the Schroedinger functional formulated by Luescher at perturbative level. By investigating spectra of the free operator and one-loop coefficient of the Schroedinger functional coupling, I…

High Energy Physics - Lattice · Physics 2010-01-21 Shinji Takeda

We present preliminary results of the running of the coupling in SU(2) gauge theory with 6 massless fundamental representation fermion flavors. We measure the coupling using the gradient flow method with Schr\"odinger functional boundary…

High Energy Physics - Lattice · Physics 2016-11-03 Viljami Leino , Teemu Rantalaiho , Kari Rummukainen , Joni M. Suorsa , Kimmo Tuominen , Sara Tähtinen

Nonperturbative determinations of the renormalization group (RG) $\beta$ function are crucial to understand properties of gauge-fermion systems at strong coupling and connect lattice simulations and the perturbative ultraviolet regime.…

High Energy Physics - Lattice · Physics 2023-01-11 Anna Hasenfratz , Claudio Rebbi , Oliver Witzel

The conductance G of an interacting nano-wire containing an impurity and coupled to non-interacting semi-infinite leads is studied using a functional renormalization group method. We obtain results for microscopic lattice models without any…

Strongly Correlated Electrons · Physics 2009-11-10 V. Meden , S. Andergassen , W. Metzner , U. Schollwoeck , K. Schoenhammer

We complete our analysis of Nf=2 QCD based on the lattice staggered fermion formulation. Using a series of Monte Carlo simulations at fixed (amq*Ls^yh) one is able to test the universality class with given critical exponent yh. This…

High Energy Physics - Lattice · Physics 2008-11-26 G. Cossu , M. D'Elia , A. Di Giacomo , C. Pica

We present an evaluation of the quark mass renormalization factor for Nf=2+1 QCD. The Schroedinger functional scheme is employed as the intermediate scheme to carry out non-perturbative running from the low energy to deep in the high energy…

High Energy Physics - Lattice · Physics 2011-03-28 Yusuke Taniguchi

We apply a recently developed renormalization group (RG) method to study synchronization in a one-dimensional chain of phase-coupled oscillators in the regime of weak randomness. The RG predicts how oscillators with randomly distributed…

Statistical Mechanics · Physics 2011-04-06 Tony E. Lee , G. Refael , M. C. Cross , Oleg Kogan , Jeffrey L. Rogers

We study the Renormalisation Group (RG) running of the non-singlet tensor operator, for $N_\mathrm{\scriptstyle f}=3$ QCD with Wilson fermions in a mixed action setup, with standard Schr\"odinger Functional (SF) boundary conditions for sea…

The gradient flow renormalized coupling offers a simple and relatively inexpensive way to calculate the step scaling function and the lattice scale, but both applications can be hindered by large lattice artifacts. Recently we introduced an…

High Energy Physics - Lattice · Physics 2015-02-02 Anna Hasenfratz

The solvability of the three-dimensional O($N$) scalar field theory in the large $N$ limit makes it an ideal toy model exhibiting "walking" behavior, expected in some SU($N$) gauge theories with a large number of fermion flavors. We study…

High Energy Physics - Lattice · Physics 2015-06-22 Sinya Aoki , Janos Balog , Peter Weisz

We present high precision results on the static quark-antiquark-potential on 32^4 and smaller lattices, using the standard Wilson action at BETA = 6.0, 6.2, 6.4, and 6.8 on the Connection Machine CM-2. Within our statistical errors (1%) we…

High Energy Physics - Lattice · Physics 2009-10-22 G. S. Bali , K. Schilling

The critical behavior of two-dimensional ${\rm O}(N)$ $\sigma$ models with $N\leq 2$ on the square, triangular, and honeycomb lattices is investigated by an analysis of the strong-coupling expansion of the two-point fundamental Green's…

High Energy Physics - Lattice · Physics 2009-10-28 Massimo Campostrini , Andrea Pelissetto , Paolo Rossi , Ettore Vicari

We study thermodynamic properties of Nf=2+1 QCD on the lattice adopting O(a)-improved Wilson quark action and Iwasaki gauge action. To cope with the problems due to explicit violation of the Poincare and chiral symmetries, we apply the…

High Energy Physics - Lattice · Physics 2020-10-02 Yusuke Taniguchi , Shinji Ejiri , Kazuyuki Kanaya , Masakiyo Kitazawa , Hiroshi Suzuki , Takashi Umeda

Renormalisation group approaches are tailor made for resolving the scale-dependence of quantum and statistical systems, and hence their phase structure and critical physics. Usually this advantage comes at the price of having to truncate…

High Energy Physics - Theory · Physics 2023-11-28 Friederike Ihssen , Jan M. Pawlowski

Our community has a deep and sophisticated understanding of phase transitions and their universal scaling functions. We outline and advocate an ambitious program to use this understanding as an anchor for describing the surrounding phases.…

Statistical Mechanics · Physics 2025-01-24 James P. Sethna , David Hathcock , Jaron Kent-Dobias , Archishman Raju

We discuss the Schr\"odinger functional in lattice QCD with staggered fermions and relate it, in the classical continuum limit, to the Schr\"odinger functional regularized with Wilson fermions. We compute the strong coupling constant…

High Energy Physics - Lattice · Physics 2009-10-30 Urs M. Heller