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Related papers: Topology in QCD

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We determine the topological susceptibility \chi_t in the topologically-trivial sector generated by lattice simulations of N_f = 2+1 QCD with overlap Dirac fermion, on a 16^3 x 48 lattice with lattice spacing ~ 0.11 fm, for five sea quark…

High Energy Physics - Lattice · Physics 2010-01-21 T. W. Chiu , S. Aoki , S. Hashimoto , T. H. Hsieh , T. Kaneko , H. Matsufuru , J. Noaki , T. Onogi , N. Yamada

We model the effects of a large number of zero and near-zero modes in the QCD partition function by using sparse chiral matrix models with an emphasis on the quenched topological susceptibility in the choice of the measure. At finite…

High Energy Physics - Lattice · Physics 2009-10-31 Romuald A. Janik , Maciej A. Nowak , Gabor Papp , Ismail Zahed

The overlap Dirac operator, which satisfies the Ginsparg-Wilson relation, realizes exact chiral symmetry on the lattice without any unphysical doubler modes. To perform the path integrals, one should, however, note that the overlap fermion…

High Energy Physics - Lattice · Physics 2007-05-23 Hidenori Fukaya

We perform hybrid Monte-Carlo (HMC) simulation of lattice QCD with $N_f=2+1+1$ domain-wall quarks at the physical point, on the $64^3 \times (64,20,16,12,10,8,6)$ lattices, each with three lattice spacings. The lattice spacings and the bare…

High Energy Physics - Lattice · Physics 2022-10-13 Yu-Chih Chen , Ting-Wai Chiu , Tung-Han Hsieh

We determine the topological susceptibility $\chi_t$ in two-flavor QCD using the lattice simulations at a fixed topological sector. The topological charge density is unambiguously defined on the lattice using the overlap-Dirac operator…

High Energy Physics - Lattice · Physics 2008-11-26 S. Aoki , T. W. Chiu , H. Fukaya , S. Hashimoto , T. H. Hsieh , T. Kaneko , H. Matsufuru , J. Noaki , K. Ogawa , T. Onogi , N. Yamada

Lattice formulations of QCD with Wilson fermions and a chirally twisted quark mass matrix provide an attractive framework for non-perturbative numerical studies. Owing to reparameterization invariance, the limiting continuum theory is just…

High Energy Physics - Lattice · Physics 2009-11-07 R. Frezzotti

We determine the conditions under which topological order survives a rapid quantum quench. Specifically, we consider the case where a quantum spin system is prepared in the ground state of the Toric Code Model and, after the quench, it…

Quantum Physics · Physics 2009-12-08 D. I. Tsomokos , A. Hamma , W. Zhang , S. Haas , R. Fazio

The behaviour of the topological susceptibility \chi in QCD with two colours and 8 flavours of quarks is studied at nonzero temperature on the lattice across the finite density transition. It is shown that the signal of \chi drops abruptly…

High Energy Physics - Lattice · Physics 2008-11-26 B. Alles , M. D'Elia , M. P. Lombardo

We show how the topological susceptibility in the Minkowskian theory of QCD is related to the corresponding quantity in the Euclidean theory, which is measured on the lattice. We discuss both the zero-temperature case (T = 0) and the…

High Energy Physics - Theory · Physics 2009-10-31 Enrico Meggiolaro

For field theories with a topological charge Q, it is often of interest to measure the topological susceptibility chi_t = ( < Q^2 > - < Q >^2 ) / V. If we manage to perform a Monte Carlo simulation where Q changes frequently, chi_t can be…

We study an effective theory for QCD at finite temperature and density which contains the leading center symmetric and center symmetry breaking terms. The effective theory is studied in a flux representation where the complex phase problem…

High Energy Physics - Lattice · Physics 2011-07-21 Ydalia Delgado Mercado , Hans Gerd Evertz , Christof Gattringer

In this paper we explore the computation of topological susceptibility and $\eta'$ meson mass in $N_f=2$ flavor QCD using lattice techniques with physical value of the pion mass as well as larger pion mass values. We observe that the…

We study the topological susceptibility, chi, in QCD with two quark flavours using lattice field configurations that have been produced with an O(a)-improved clover quark action. We find clear evidence for the expected suppression at small…

High Energy Physics - Lattice · Physics 2013-05-29 UKQCD , QCDSF Collaborations , : , A. Hart

We perform dynamical QCD simulations with $n_f=2$ overlap fermions by hybrid Monte-Carlo method on $6^4$ to $8^3\times 16$ lattices. We study the problem of topological sector changing. A new method is proposed which works without…

High Energy Physics - Lattice · Physics 2009-11-11 G. I. Egri , Z. Fodor , S. D. Katz , K. K. Szabo

We investigate topology in lattice simulations of QCD with two flavours of dynamical Wilson fermions. At various sea quark masses we find reasonable agreement between results for the topological charge from fermionic and gluonic…

High Energy Physics - Lattice · Physics 2008-11-26 Gunnar S. Bali , Norbert Eicker , Thomas Lippert , Hartmut Neff , Boris Orth , Klaus Schilling , Thorsten Struckmann , Jochen Viehoff

We calculate the topological susceptibility at 2.5 Tc and 4.1 Tc in SU(3) pure Yang-Mills theory. We define topology with the help of gradient flow and we largely overcome the problem of poor statistics at high temperatures by applying a…

High Energy Physics - Lattice · Physics 2018-09-26 P. Thomas Jahn , Guy D. Moore , Daniel Robaina

In this proceeding contribution we report on a test of the famous Witten-Veneziano formula using lattice techniques. We perform dedicated quenched simulations and apply the spectral projector method to determine the topological…

High Energy Physics - Lattice · Physics 2015-11-04 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen , Konstantin Ottnad , Carsten Urbach

We compare the approach to the chiral transition line $~\kappa_c(\bt)~$ in quenched and full compact lattice QED with Wilson fermions within the confinement phase, especially in the pseudoscalar sector of the theory. We show that in the…

High Energy Physics - Lattice · Physics 2009-10-28 A. Hoferichter , V. K. Mitrjushkin , M. Müller--Preussker , H. Stüben

We show that the assumption of non-zero topological susceptibility of the vacuum in a fermion-free version of a theory, such as gravity or QCD, suffices to conclude the following: Once N massless fermion flavors are added to the theory,…

High Energy Physics - Theory · Physics 2017-05-19 Gia Dvali

We use the overlap formalism to define a topological index on the lattice. We study the spectral flow of the hermitian Wilson-Dirac operator and identify zero crossings with topological objects. We determine the topological susceptibility…

High Energy Physics - Lattice · Physics 2009-10-31 Robert G. Edwards , Urs M. Heller , Rajamani Narayanan