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Related papers: The Sign Problem is the Solution

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A continuum expression for the trace of the massive dressed-quark propagator is used to explicate a connection between the infrared limit of the QCD Dirac operator's spectrum and the quark condensate appearing in the operator product…

Nuclear Theory · Physics 2010-03-04 K. Langfeld , R. Pullirsch , H. Markum , C. D. Roberts , S. M. Schmidt

We consider an elliptic self-adjoint first order differential operator acting on pairs (2-columns) of complex-valued half-densities over a connected compact 3-dimensional manifold without boundary. The principal symbol of our operator is…

Spectral Theory · Mathematics 2015-05-05 Olga Chervova , Robert J. Downes , Dmitri Vassiliev

We compare the low-lying spectrum of the staggered Dirac operator in the confining phase of compact U(1) gauge theory on the lattice to predictions of chiral random matrix theory. The small eigenvalues contribute to the chiral condensate…

High Energy Physics - Lattice · Physics 2009-10-31 B. A. Berg , H. Markum , R. Pullirsch , T. Wettig

We consider an elliptic self-adjoint first order pseudodifferential operator acting on columns of m complex-valued half-densities over a connected compact n-dimensional manifold without boundary. The eigenvalues of the principal symbol are…

Analysis of PDEs · Mathematics 2012-05-01 Olga Chervova , Robert J. Downes , Dmitri Vassiliev

In this note, we consider the Dirac operator $D$ on a Riemannian symmetric space $M$ of noncompact type. Using representation theory we show that $D$ has point spectrum iff the $\hat A$-genus of its compact dual does not vanish. In this…

Differential Geometry · Mathematics 2008-09-16 S. Goette , U. Semmelmann

The microscopic spectral density of the Hermitian Wilson-Dirac operator is computed numerically in quenched lattice QCD. We demonstrate that the results given for fixed index of the Wilson-Dirac operator can be matched by the predictions…

High Energy Physics - Lattice · Physics 2013-05-30 P. H. Damgaard , U. M. Heller , K. Splittorff

The spectral propinquity is a distance, up to unitary equivalence, on the class of metric spectral triples. We prove in this paper that if a sequence of metric spectral triples converges for the propinquity, then the spectra of the Dirac…

Operator Algebras · Mathematics 2024-07-15 Frederic Latremoliere

At nonzero density the eigenvalues of the Dirac operator move into the complex plane, while its singular values remain real and nonnegative. In QCD-like theories, the singular-value spectrum carries information on the diquark (or pionic)…

High Energy Physics - Lattice · Physics 2012-12-11 Takuya Kanazawa , Tilo Wettig , Naoki Yamamoto

The necessary and sufficient conditions are given for a sequence of complex numbers to be the periodic (or antiperiodic) spectrum of non-self-adjoint Dirac operator.

Spectral Theory · Mathematics 2021-04-21 Alexander Makin

In this preliminary study, we examine the chiral properties of the parametrized Fixed-Point Dirac operator D^FP, see how to improve its chirality via the Overlap construction, measure the renormalized quark condensate Sigma and the…

High Energy Physics - Lattice · Physics 2015-06-25 P. Hasenfratz , S. Hauswirth , K. Holland , T. Jorg , F. Niedermayer

We consider a two-dimensional massless Dirac operator coupled to a magnetic field $B$ and an electric potential $V$ growing at infinity. We find a characterization of the spectrum of the resulting operator $H$ in terms of the relation…

Mathematical Physics · Physics 2014-05-28 Josef Mehringer , Edgardo Stockmeyer

We study theoretically the level shift of the Dirac oscillator perturbed by any sharply peaked potential approaching a surface delta potential. A Green function method is used to obtain closed expressions for all partial waves and parities.

Quantum Physics · Physics 2026-02-24 J. Munárriz , F. Domínguez-Adame , R. P. A. Lima

Investigating the canonical problem of a periodic multilayered stack containing isotropic chiral layers, we homogenized it as a uniaxial bianisotropic medium and derived its effective constitutive parameters. The stack shows a resonant…

Optics · Physics 2009-05-08 S. Anantha Ramakrishna , Akhlesh Lakhtakia

In this paper, we study a singular perturbation of a problem used in dimension two to model graphene or in dimension three to describe the quark confinement phenomenon in hadrons. The operators we consider are of the form $H + M\beta V…

Spectral Theory · Mathematics 2019-09-10 Badreddine Benhellal

In this talk we review some recent results from random matrix models as applied to some non-perturbative issues in QCD. All of the issues we will discuss touched upon the important phenomenon related to the spontaneous breaking of chiral…

High Energy Physics - Phenomenology · Physics 2007-05-23 Romuald A. Janik , Maciej A. Nowak , Gabor Papp , Ismail Zahed

Taking into account pseudoscalar as well as scalar condensates, we reexamine the chiral restoration path on the chiral manifold. We shall see both condensates coherently produce a density wave at a certain density, which delays chiral…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Tatsumi , E. Nakano

We discuss the sign problem in QCD at nonzero chemical potential and its relation with chiral symmetry breaking and the spectrum of the Dirac operator using the framework of chiral random matrix theory. We show that the Banks-Casher formula…

High Energy Physics - Theory · Physics 2009-01-06 K. Splittorff , J. J. M. Verbaarschot

In this work we study the Dirac equation on the cosmic string background, which models a one--dimensional topological defect in the spacetime. We first define the Dirac operator in this setting, classifying all of its selfadjoint…

Analysis of PDEs · Mathematics 2025-01-22 Piero D'Ancona , Zhiqing Yin , Junyong Zhang

We demonstrate that the sequence of distorted commensurate phases observed in tilted chiral smectics is explained by the gain in electrostatic energy due to the lock-in of the unit cell to a number of layers which is the integer closest to…

Soft Condensed Matter · Physics 2015-05-18 Jean-Paul Marcerou

We study the inverse spectral problems of recovering Dirac-type functional-differential operator with two constant delays $a_1$ and $a_2$ not less than one-third of the interval. It has been proved that the operator can be recovered…

Spectral Theory · Mathematics 2023-08-17 Biljana Vojvodić , Nebojša Djurić , Vladimir Vladičić