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Related papers: The gradient flow of the Dirac spectrum

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We investigate numerically the spectral flow introduced by Adams for the staggered Dirac operator on realistic gauge configurations. We study both the unimproved and the HISQ Dirac operators. We compare the spectral flow index with the…

High Energy Physics - Lattice · Physics 2011-11-16 E. Follana , V. Azcoiti , G. Di Carlo , A. Vaquero

We present simulation results for lattice QCD with chiral fermions in small volumes, where the epsilon-expansion of chiral perturbation theory applies. Our data for the low lying Dirac eigenvalues, as well as mesonic correlation functions,…

High Energy Physics - Lattice · Physics 2009-11-11 W. Bietenholz , T. Chiarappa , K. Jansen , K. -I. Nagai , S. Shcheredin

We calculate the chiral condensate of QCD with 2, 2+1 and 3 flavors of sea quarks. Lattice QCD simulations are performed employing dynamical overlap fermions with up and down quark masses covering a range between 3 and 100 MeV. On L ~…

High Energy Physics - Lattice · Physics 2015-03-17 H. Fukaya , S. Aoki , T. W. Chiu , S. Hashimoto , T. Kaneko , J. Noaki , T. Onogi , N. Yamada

We investigate the spectral properties of the Wilson Dirac operator in quenched QCD in the microscopic regime. We distinguish the topological sectors using the index as determined by the Wilson flow method. Consequently, the distributions…

High Energy Physics - Lattice · Physics 2012-01-04 Albert Deuzeman , Urs Wenger , Jair Wuilloud

We study the frequency dependence of all the chiral vortical and magnetic conductivities for a relativistic gas of free chiral fermions and for a strongly coupled conformal field theory with holographic dual in four dimensions. Both systems…

High Energy Physics - Phenomenology · Physics 2014-10-01 Karl Landsteiner , Eugenio Megias , Francisco Peña Benítez

In the framework of Euclidean QCD on a torus, we study the spectrum of the Dirac operator through inverse moments of its eigenvalues, averaged over topological sets of gluonic configurations. The large-volume dependence of these sums is…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sebastien Descotes , Jan Stern

We show that plane parabolic flow in a microfluidic channel causes nonmotile helically-shaped bacteria to drift perpendicular to the shear plane. Net drift results from the preferential alignment of helices with streamlines, with a…

Mesoscale and Nanoscale Physics · Physics 2010-04-07 Marcos , Henry C. Fu , Thomas R. Powers , Roman Stocker

We compare the eigenvalue spectra of the Dirac operator from a simulation with two mass degenerate dynamical chirally improved fermions with Random Matrix Theory. Comparisons with distribution of k-th eigenvalues (k=1,2) in fixed…

High Energy Physics - Lattice · Physics 2008-11-26 C. B. Lang , Pushan Majumdar , Wolfgang Ortner

We investigate the contribution of instantons to the eigenvalue spectrum of the Dirac operator in quenched QCD. The instanton configurations that we use have been derived, elsewhere, from cooled SU(3) lattice gauge fields and, for…

High Energy Physics - Lattice · Physics 2016-08-25 U. Sharan , M. Teper

Non-singlet chiral Ward identities for fermionic operators at positive flow-time are derived using standard techniques based on local chiral variations of the action and of local operators. The gradient flow formalism is applied to twisted…

High Energy Physics - Lattice · Physics 2014-02-11 Andrea Shindler

We present the results of our computation of the chiral condensate with $N_f=2$ and $N_f=2+1+1$ flavours of maximally twisted mass fermions. The condensate is determined from the Dirac operator spectrum, applying the spectral projector…

High Energy Physics - Lattice · Physics 2013-12-20 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen

The multifractal scaling exponents are calculated for the critical wave function of a two-dimensional Dirac fermion in the presence of a random magnetic field. It is shown that the problem of calculating the multifractal spectrum maps into…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Horacio E. Castillo , Claudio de C. Chamon , Eduardo Fradkin , Paul M. Goldbart , Christopher Mudry

Dynamical chiral symmetry breaking is described within the linear sigma model of QCD coupled to quarks. The main technical tool used for this intrinsically non--perturbative problem is an exact renormalization group equation for the quantum…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. -U. Jungnickel

We study the expansion dynamics of a quark-antiquark plasma droplet from an initial state with restored chiral symmetry. The calculations are made within the linear $\sigma$ model scaled with an additional scalar field representing the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Igor N. Mishustin , Ove Scavenius

The spectral density of euclidean Dirac operator is investigated in partially quenched QCD with arbitrary quark masses. A representation of scalar and pseudoscalar correlators in terms of the spectral density is discussed. The spectral…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Zyablyuk

The unquenched spectral density of the Dirac operator at $\mu\neq0$ is complex and has oscillations with a period inversely proportional to the volume and an amplitude that grows exponentially with the volume. Here we show how the…

High Energy Physics - Lattice · Physics 2007-05-23 J. C. Osborn , K. Splittorff , J. J. M. Verbaarschot

The heavy quark diffusion coefficient is encoded in the spectral functions of the chromo-electric and the chromo-magnetic correlators, of which the latter describes the T/M contribution. We study these correlators at two different…

High Energy Physics - Lattice · Physics 2022-12-22 Viljami Leino , Nora Brambilla , Julian Mayer-Steudte , Peter Petreczky

We study the non-linear current response of a Dirac model that is coupled to two time-periodic electro-magnetic fields with different frequencies. We distinguish between incommensurable and commensurable frequencies, the latter…

Mesoscale and Nanoscale Physics · Physics 2020-11-17 Sigmund Kohler , Tobias Stauber

We derive the spectrum of the Dirac operator for the linear sigma-model with quarks in the large N_c approximation using renormalization group flow equations. For small eigenvalues, the Banks-Casher relation and the vanishing linear term…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. Spitzenberg , K. Schwenzer , H. -J. Pirner

In recent work [1] we uncovered intriguing connections between Otto's characterisation of diffusion as entropic gradient flow [16] on one hand and large-deviation principles describing the microscopic picture (Brownian motion) on the other.…

Analysis of PDEs · Mathematics 2014-03-05 Stefan Adams , Nicolas Dirr , Mark A. Peletier , Johannes Zimmer