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Related papers: The Aoki phase revisited

200 papers

I conjecture on the phase structure expected for lattice gauge theory with two flavors of Wilson fermions, concentrating on large values of the hopping parameter. Numerous phases are expected, including the conventional confinement and…

High Energy Physics - Lattice · Physics 2008-02-03 Michael Creutz

In this paper, we examine the phase diagram of quenched QCD with two flavors of Wilson fermions, proposing the following microscopic picture. The super-critical regions inside and outside the Aoki phase are characterized by the existence of…

High Energy Physics - Lattice · Physics 2008-11-26 Maarten Golterman , Yigal Shamir

We investigate the phase structure of three-flavor QCD in the presence of finite quark chemical potential $\mu/T\lesssim1.2$ by using the non-perturbatively $O(a)$ improved Wilson fermion action on lattices with a fixed temporal extent…

High Energy Physics - Lattice · Physics 2015-12-30 Xiao-Yong Jin , Yoshinobu Kuramashi , Yoshifumi Nakamura , Shinji Takeda , Akira Ukawa

Three-flavor QCD simulation with the $O(a)$-improved Wilson fermion action is made employing an exact fermion algorithm developed for odd number of quark flavors. For the plaquette gauge action, an unexpected first-order phase transition is…

We present numerical results for the phase diagram of lattice QCD at finite temperature in the formulation with twisted mass Wilson fermions and a tree-level Symanzik-improved gauge action. Our simulations are performed on lattices with…

High Energy Physics - Lattice · Physics 2010-04-14 E. -M. Ilgenfritz , K. Jansen , M. P. Lombardo , M. Müller-Preußker , M. Petschlies , O. Philipsen , L. Zeidlewicz

We present an update of our study of the phase diagram of two-flavour QCD at zero baryon density with dynamical $O(a)$ improved Wilson quarks. All simulations are done on lattices with a temporal extent of $N_t=16$ and spatial extent…

High Energy Physics - Lattice · Physics 2013-11-01 Bastian B. Brandt , Anthony Francis , Harvey B. Meyer , Owe Philipsen , Hartmut Wittig

We consider the phase diagram of twisted mass Wilson fermions of two-flavor QCD in the parameter space of the quark mass, the isospin chemical potential, the twist angle and the lattice spacing. This work extends earlier studies in the…

High Energy Physics - Lattice · Physics 2016-05-11 Oliver Janssen , Mario Kieburg , K. Splittorff , Jacobus J. M. Verbaarschot , Savvas Zafeiropoulos

We investigate the parity-broken phase structure for staggered and naive fermions in the Gross-Neveu model as a toy model of QCD. We consider a generalized staggered Gross-Neveu model including two types of four-point interactions. We use…

High Energy Physics - Lattice · Physics 2011-05-24 Michael Creutz , Taro Kimura , Tatsuhiro Misumi

Results are presented from a numerical study of lattice QCD with gauge group SU(2) and two flavors of Wilson fermion at non-zero quark chemical potential mu >> T. Studies of the equation of state, the superfluid condensate, and the Polyakov…

Nuclear Theory · Physics 2008-11-26 Simon Hands , Seyong Kim , Jon-Ivar Skullerud

We explore aspects of the phase structure of SU(2) and SU(3) lattice gauge theories at strong coupling with many flavours $N_f$ of Wilson fermions in the fundamental representation, including the relevance to recent searches for a conformal…

High Energy Physics - Lattice · Physics 2010-11-04 Kei-ichi Nagai , Maria Georgina Carrillo-Ruiz , Gergana Koleva , Randy Lewis

In this talk we determine the phase diagram and pion spectrum for Wilson and twisted-mass fermions in the presence of non-degeneracy between the up and down quark and discretization errors. We find that the CP-violating phase of the…

High Energy Physics - Lattice · Physics 2014-11-06 Derek P. Horkel , Stephen R. Sharpe

The introduction of a chirally twisted mass term has been proposed as an attractive approach to O(a) improvement of Quantum Chromodynamics with Wilson fermions on a lattice. For numerical simulation projects it is important to know the…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster

The QCD partition function for the Wilson Dirac operator, $D_W$, at nonzero lattice spacing $a$ can be expressed in terms of a chiral Lagrangian as a systematic expansion in the quark mass, the momentum and $a^2$. Starting from this chiral…

High Energy Physics - Lattice · Physics 2011-07-15 G. Akemann , P. H. Damgaard , K. Splittorff , J. J. M. Verbaarschot

We determine the phase diagram and pion spectrum for Wilson and twisted-mass fermions in the presence of non-degeneracy between the up and down quark and discretization errors, using Wilson and twisted-mass chiral perturbation theory. We…

High Energy Physics - Lattice · Physics 2014-12-03 Derek P. Horkel , Stephen R. Sharpe

We use the effective chiral Lagrangian to analyze the phase diagram of two-flavor twisted mass lattice QCD as a function of the normal and twisted masses, generalizing previous work for the untwisted theory. We first determine the chiral…

High Energy Physics - Lattice · Physics 2009-11-10 Stephen R. Sharpe , Jackson M. S. Wu

We construct 2D non-$\gamma_{5}$hermiticity fermions based on the minimal doubling fermion. We investigate symmetries, reflection positivity, eigenvalue distribution and the number of poles for our fermions. As simple tests for application…

High Energy Physics - Lattice · Physics 2014-03-03 Syo Kamata , Hidekazu Tanaka

We present first results of a study of two flavour QCD with Wilson fermions at finite temperature. We have used tree level Symanzik improvement in both the gauge and fermion part of the action. In a first step we explore the phase diagramm…

High Energy Physics - Lattice · Physics 2009-10-30 F. Karsch , E. Laermann , M. Oevers , P. Schmidt

In this talk, I reported on recent work on the Aoki phase diagram for quenched QCD with two flavors of Wilson fermions. Part of this work was done in collaboration with Yigal Shamir, and a shorter account of this part appeared recently. In…

High Energy Physics - Lattice · Physics 2009-11-10 Maarten Golterman

We explore the phase diagram of two flavour QCD at vanishing chemical potential using dynamical O(a)-improved Wilson quarks. In the approach to the chiral limit we use lattices with a temporal extent of N_t=16 and spatial extent L=32,48 and…

High Energy Physics - Lattice · Physics 2012-10-26 Bastian B. Brandt , Anthony Francis , Harvey B. Meyer , Owe Philipsen , Hartmut Wittig

The nature of the phase transition in the lattice Gross-Neveu model with Wilson fermions is investigated using a new analytical technique. This involves a new type of weak coupling expansion which focuses on the partition function zeroes of…

High Energy Physics - Lattice · Physics 2009-11-07 R. Kenna , J. C. Sexton