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Related papers: Monopole and instanton effects in QCD

200 papers

We perform a study of the non-perturbative dynamics of the light-quark sector of QCD, based on some recent results of lattice simulations with chiral fermions. We analyze some correlators that are designed to probe the Dirac structure of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Pietro Faccioli , Thomas A. DeGrand

Magnetic monopoles are known to emerge as leading non-perturbative fluctuations in the lattice version of non-Abelian gauge theories in some gauges. In terms of the Dirac quantization condition, these monopoles have magnetic charge |Q_M|=2.…

High Energy Physics - Theory · Physics 2015-06-25 M. N. Chernodub , F. V. Gubarev , M. I. Polikarpov , V. I. Zakharov

Chiral symmetry in massless QCD is believed to be broken spontaneously. We discuss a possibility that the chiral symmetry is explicitly broken by QCD monopoles which appear only in strong coupled QCD. Namely, the monopole quark interaction…

High Energy Physics - Phenomenology · Physics 2019-09-02 Aiichi Iwazaki

We analyze topological objects in pure QCD in the presence of external quarks by calculating the distributions of instanton and monopole densities around static color sources. We find a suppression of the densities close to external sources…

High Energy Physics - Theory · Physics 2016-11-03 St. Thurner , H. Markum , W. Sakuler

In the framework of the instanton vacuum model we evaluate the Chiral Perturbation Theory (ChPT) low-energy constants h_3,l_7. We found that in the instanton vacuum model the constant l_7 is very sensitive to the shape of the instanton and…

High Energy Physics - Phenomenology · Physics 2010-04-14 K. Goeke , M. Musakhanov , M. Siddikov

Chiral monopoles are hedgehoglike structures in local chiral condensates in QCD. These monopoles are (i) made of quark and gluon fields; (ii) explicitly gauge-invariant; and (iii) they carry quantized and conserved chromomagnetic charge. We…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. N. Chernodub

We present simulation results for lattice QCD with light pions. For the quark fields we apply chirally symmetric lattice Dirac operators, in particular the overlap hypercube operator, along with the standard overlap operator for comparison.…

High Energy Physics - Lattice · Physics 2007-05-23 W. Bietenholz , S. Shcheredin

We investigate the leading-twist light-cone distribution amplitudes for the pion and kaon, based on the nonlocal chiral quark model from the instanton vacuum. Effects of explicit flavor SU(3)-symmetry breaking are taken into account. The…

High Energy Physics - Phenomenology · Physics 2009-11-11 Seung-il Nam , Hyun-Chul Kim , Atsushi Hosaka , M. M. Musakhanov

The Dirac spin liquid (DSL) is a two-dimensional (2D) fractionalized Mott insulator featuring massless Dirac spinon excitations coupled to a compact $U(1)$ gauge field, which allows for flux-tunneling instanton events described by magnetic…

Strongly Correlated Electrons · Physics 2024-05-08 G. Shankar , Joseph Maciejko

This talk is a review of our studies of instantons and their properties as seen in our lattice simulations of SU(2) gauge theory. We have measured the topological susceptibility and the size distribution of instantons in the QCD vacuum. We…

High Energy Physics - Lattice · Physics 2016-09-01 T. DeGrand , Anna Hasenfratz , Tamas Kovacs

We (try to) pedagogically explain how monopoles arise in QCD, why maximal Abelian(MA) gauge is ``special'' for monopole study, the Abelian projection in MA gauge, its resultant degrees of freedom(photons, monopoles and charged matter…

High Energy Physics - Phenomenology · Physics 2011-04-15 Ken Yee

Pseudoscalar correlator is measured in a singular (monopole dominant) and a regular (photon dominant) parts of a maximal abelian field on SU(2) lattice. In the abelian field and its singular part, light pseudoscalar boson are observed…

High Energy Physics - Lattice · Physics 2016-11-03 O. Miyamura , S. Origuchi

Magnetic monopoles --- particles that behave as isolated north or south magnetic poles --- have been the subject of speculation since the first detailed observations of magnetism several hundred years ago. Numerous theoretical…

Quantum Gases · Physics 2014-08-15 M. W. Ray , E. Ruokokoski , S. Kandel , M. Möttönen , D. S. Hall

The pion electric polarizability, \alpha^E_\pi^\pm, the leading order hadronic contribution to the muon anomalous magnetic moment, $a_\mu^{hvp 1} $, and the ratio of the difference to the sum of vector and axial-vector correlators,…

High Energy Physics - Phenomenology · Physics 2017-08-23 A. E. Dorokhov

To understand the relation between the chiral symmetry breaking and monopoles, the chiral condensate which is the order parameter of the chiral symmetry breaking is calculated in the $\overline{\mbox{MS}}$ scheme at 2 [GeV]. First, we add…

High Energy Physics - Lattice · Physics 2016-02-04 Adriano Di Giacomo , Masayasu Hasegawa , Fabrizio Pucci

We use low lying eigenvectors of the overlap-Dirac operator as a probe of the QCD vacuum. If instantons play a significant role one would expect the low lying eigenmodes of the overlap-Dirac operator to consist mainly of the mixed ``would…

High Energy Physics - Lattice · Physics 2014-11-17 Robert G. Edwards , Urs M. Heller

Non-Abelian gauge fields having a line-singularity of the Dirac type lead us to violation of the non-Abelian Bianchi identity. The violation as an operator is equivalent to violation of Abelian-like Bianchi identities corresponding to eight…

High Energy Physics - Lattice · Physics 2023-05-17 Tsuneo Suzuki

We pursue the intriguing possibility that larger-size instantons build up diffractive scattering, with the marked instanton-size scale $<\rho> \approx 0.5$ fm being reflected in the conspicuous ``geometrization'' of soft QCD. As an explicit…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. Schrempp , A. Utermann

A projection (gauge) independent formulation of the monopole dominance, discovered in lattice QCD for the maximal abelian projection, is given. A new dynamical abelian projection of continuum QCD, which does not rely on any explicit gauge…

High Energy Physics - Theory · Physics 2007-05-23 Sergei V. Shabanov

We study the role of direct (i.e. small-scale) instantons in QCD correlation functions for the nucleon. They generate sizeable, nonperturbative corrections to the conventional operator product expansion, which improve the quality of both…

High Energy Physics - Phenomenology · Physics 2009-10-22 Hilmar Forkel , Manoj K. Banerjee