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Related papers: Chiral Symmetry Breaking by Instantons

200 papers

We propose a new way of understanding how chiral symmetry is realized in the high temperature phase of QCD. Based on the finding that a simple free instanton gas precisely describes the details of the lowest part of the spectrum of the…

High Energy Physics - Lattice · Physics 2024-05-24 Tamas G. Kovacs

We calculate the contribution of the instanton -- anti-instanton ($I\bar I$) pairs to the vacuum energy of QCD-like theories with $N_f$ light fermions using the saddle point method. We find a qualitative change of the behavior: for $N_f \ge…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. Velkovsky , E. Shuryak

We derive a non-local Nambu-Jona-Lasinio model from QCD with a form factor exactly obtained in the infrared limit. With this model, having all the parameters properly fixed through those of QCD, we consider the case of finite temperature…

High Energy Physics - Phenomenology · Physics 2015-03-19 Marco Frasca

The instanton vacuum provides an effective description of chiral symmetry breaking by local topological fluctuations of the gauge fields, as observed in lattice QCD simulations. The resulting effective dynamics at momenta below $1/\bar\rho…

High Energy Physics - Phenomenology · Physics 2025-03-18 Christian Weiss

This study is part of a research program aimed to investigate the relations between instantons, monopoles, and chiral symmetry breaking. Monopoles are important 3-dimensional topological configurations existing in QCD, which are believed to…

High Energy Physics - Lattice · Physics 2015-03-31 Adriano Di Giacomo , Masayasu Hasegawa

We review the Nambu-Jona-Lasinio (NJL) approach to the dynamical breaking of chiral symmetry in Quantum Chromodynamics (QCD). The subjects treated in Part I include the vacuum structure of QCD, mass spectra and coupling constants of…

High Energy Physics - Phenomenology · Physics 2010-11-01 T. Hatsuda , T. Kunihiro

We calculate the spectral density of the Dirac operator over an ensemble of configurations composed of overlapping instantons and anti-instantons. We find evidence that the spectral density diverges in the limit of small eigenvalues. This…

High Energy Physics - Lattice · Physics 2009-10-31 U. Sharan , M. Teper

Paradigme shift in gauge topology, from instantons to their constituents -- instanton-dyons -- has recently lead to very significant advances. Like instantons, they have fermionic zero modes, and their collectivization at sufficiently high…

Nuclear Theory · Physics 2017-10-10 Edward Shuryak

Chiral symmetry breaking is calculated as a function of cooling in quenched lattice QCD. A non-zero signal is found for the chiral condensate beyond one hundred cooling steps, suggesting that there is chiral symmetry breaking associated…

High Energy Physics - Lattice · Physics 2009-10-28 R. M. Woloshyn , F. X. Lee

The purpose of this study is to investigate the relations between instantons, monopoles, and Chiral symmetry breaking. The monopoles are important topological configurations existing in QCD which are believed to produce colour confinement.…

High Energy Physics - Lattice · Physics 2015-05-15 Adriano Di Giacomo , Masayasu Hasegawa

Using lattice QCD we study the spectrum of low-lying fermion eigenmodes. According to the Banks-Casher relation, accumulation of the low-mode is responsible for the spontaneous breaking of chiral symmetry in the QCD vacuum. On the lattice…

High Energy Physics - Phenomenology · Physics 2014-11-20 Shoji Hashimoto

In this work we present the results from numerical simulations of an interacting ensemble of instanton-dyons in the $SU(3)$ gauge group with $N_f=2$ flavors of massless quarks. Dynamical quarks are included via the effective interactions…

High Energy Physics - Phenomenology · Physics 2021-12-01 Dallas DeMartini , Edward Shuryak

Confining configurations are introduced into the standard instanton vacuum model. This drastically improves theoretical properties of the vacuum: instanton size density $d(\rho)$ stabilizes at $\rho\sim 0.2 fm$, all chiral effects are…

High Energy Physics - Phenomenology · Physics 2009-07-28 Yu. A. Simonov

This series of three lectures covers (a) a basic introduction to symmetry breaking in general and chiral symmetry breaking in QCD, (b) an overview of the present status of lattice data and the knowlegde that we have at finite temperature…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. P. Klevansky

This project aims to give indications to find monopole and instanton effects in QCD on the observables by experiments. First, we add the monopole and anti-monopole to the QCD vacuum of the quenched SU(3) and calculate the physical…

High Energy Physics - Lattice · Physics 2022-04-01 Masayasu Hasegawa

Based on the AdS/CFT correspondence we study the breaking of the chiral symmetry in QCD using a simple five dimensional model. The model gives definite predictions for the spectrum of vector mesons, their decay constants and interactions as…

High Energy Physics - Phenomenology · Physics 2008-11-26 Leandro Da Rold , Alex Pomarol

Paradigm shift in gauge topology at finite temperatures, from the instantons to their constituents -- instanton-dyons -- has recently lead to studies of their ensembles and very significant advances. Like instantons, they have fermionic…

High Energy Physics - Lattice · Physics 2018-04-18 E. Shuryak

Chiral quark model with a broken-U(3) flavor symmetry can be interpreted as the effective theory of the instanton-dominated non-perturbative QCD. This naturally suggests the possibility of a negative singlet/octet coupling ratio, which has…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. P. Cheng , Ling-Fong Li

The spontaneous breaking of chiral symmetry (SBCS) is one of the most important phenomena of hadron physics. It defines the properties of all the light mesons and baryons. The Chiral Perturbation Theory (ChPT) encodes QCD hadronic…

High Energy Physics - Phenomenology · Physics 2012-12-19 Mirzayusuf Musakhanov

Spontaneous breaking of chiral symmetry in QCD has traditionally been inferred indirectly through low-energy theorems and comparison with experiments. Thanks to the understanding of an unexpected connection between chiral Random Matrix…

High Energy Physics - Phenomenology · Physics 2015-05-27 P. H. Damgaard