English
Related papers

Related papers: A BCS Gap on the Lattice

200 papers

We explore the possibility that fermionic dark matter undergoes a BCS transition to form a superfluid. This requires an attractive interaction between fermions and we describe a possible source of this interaction induced by torsion. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-13 Stephon Alexander , Sam Cormack

The structure of the quark and lepton masses and mixing angles provides one of the few windows we have on the underlying physics generating the \sm. In an attempt to identify the underlying symmetry group we look for the simplest gauge…

High Energy Physics - Phenomenology · Physics 2011-07-19 Luis E. Ibanez , G. G. Ross

We study SU(2) lattice gauge theory at non-zero chemical potential with one staggered quark flavor in the adjoint representation. In this model the fermion determinant, although real, can be both positive and negative. We have performed…

High Energy Physics - Lattice · Physics 2011-09-13 S. Hands , I. Montvay , L. Scorzato , J. Skullerud

We discuss the quark condensate of the vacuum inside the baryon. We analyze the 1+1 dimensional chiral bag in analogy with the realistic 3+1 dimensional one. The Nambu--Jona-Lasinio (NJL) type interaction is used to investigate the quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Yasui , A. Hosaka , M. Oka

We study two-color QCD with two flavors of Wilson fermion as a function of quark chemical potential mu and temperature T, for two different lattice spacings and two different quark masses. We find that the quarkyonic region, where the…

High Energy Physics - Lattice · Physics 2020-04-15 Tamer Boz , Pietro Giudice , Simon Hands , Jon-Ivar Skullerud

Dynamical symmetry breaking can happen through a Higgs mechanism but also spontaneously within a strongly-enough coupled theory. We treat a field-theoretical quark model of QCD based on a linear+Coulomb Cornell potential (to account for the…

In this paper we study a model of s-wave marginal Fermi liquid superconductor at two dimensions. Besides the usual Bardeen-Cooper-Schrieffer(BCS) point attractive interaction, the fermions in our system also interact {\em via} a long range…

Superconductivity · Physics 2007-05-23 Y. L. Liu , T. K. Ng

QCD at non-zero chemical potential ($\mu$) for quark number has a complex fermion determinant and thus standard simulation methods for lattice QCD cannot be applied. We therefore simulate this theory using the Complex-Langevin algorithm…

High Energy Physics - Lattice · Physics 2015-10-22 D. K. Sinclair , J. B. Kogut

It is well known that the covariant coupling of fermionic matter to gravity induces a four-fermion interaction. The presence of this term in a homogenous and isotropic space-time results in a BCS-like Hamiltonian and the formation of a…

High Energy Physics - Theory · Physics 2007-05-23 Stephon H. S. Alexander , Deepak Vaid

We present a lattice simulation study of large $N_c$ regularities of meson and baryon spectroscopy in $SU(N_c)$ gauge theory with two flavors of dynamical fundamental representation fermions. Systems investigated include $N_c=2$, 3, 4, and…

High Energy Physics - Lattice · Physics 2017-01-04 Thomas DeGrand , Yuzhi Liu

We present the lattice QCD simulation with the 2+1+1 flavor full QCD ensembles using near-physical quark masses and different spatial sizes $L$, at $a\sim$ 0.055 fm. The results suggest that spontaneous chiral symmetry breaking is…

High Energy Physics - Lattice · Physics 2024-03-05 Xiaolan Meng , Bolun Hu , Yi-Bo Yang

We derive a new Banks-Casher-type relation which relates the density of complex Dirac eigenvalues at the origin to the BCS gap of quarks at high density. Our relation is applicable to QCD and QCD-like theories without a sign problem, such…

High Energy Physics - Lattice · Physics 2013-07-18 Takuya Kanazawa , Tilo Wettig , Naoki Yamamoto

In the continuum, the single flavor massless Schwinger model has an exact global axial $U(1)$ symmetry in the sector of perturbative gauge fields. This symmetry is explicitly broken by gauge fields with nonzero topological charge inducing a…

High Energy Physics - Lattice · Physics 2016-09-01 Rajamani Narayanan , Herbert Neuberger , Pavlos Vranas

We investigate chiral symmetry breaking in a model of Dirac fermions with a complexified coupling constant whose imaginary part represents dissipation. We introduce a chiral chemical potential and observe that for real coupling a…

High Energy Physics - Theory · Physics 2021-03-16 Takuya Kanazawa

Neutral $B$ meson mixing matrix elements and $B$ meson decay constants are calculated. Static approximation is used for $b$ quark and domain-wall fermion formalism is employed for light quarks. The calculations are carried out on $2+1$…

High Energy Physics - Lattice · Physics 2015-06-30 Yasumichi Aoki , Tomomi Ishikawa , Taku Izubuchi , Christoph Lehner , Amarjit Soni

We present results of lattice computations using overlap fermions on a twisted mass background. $N_f=2$ full QCD gauge configurations have been produced by the ETM Collaboration with very light pions (down to less than 300 MeV), with small…

High Energy Physics - Lattice · Physics 2009-04-14 Nicolas Garron , Luigi Scorzato

The thermodynamics of massless ideal gas of overlap quarks has been investigated numerically for both zero and nonzero baryon chemical potential $\mu$. While the parameter M has been shown to be irrelevant in the continuum limit, it is…

High Energy Physics - Lattice · Physics 2008-11-26 R. V. Gavai , Sayantan Sharma

By using a well established 'ab initio' theoretical approach developed in the past to quantitatively study the superconductivity of condensed matter systems, which is based on the Kohn-Sham Density Functional theory, I study the superfluid…

Quantum Gases · Physics 2016-06-01 Francesco Ancilotto

We perform lattice simulations of two flavors QCD using the optimal domain-wall fermion, in which the chiral symmetry is preserved to a good precision ($ m_{res} \sim 0.3 $ MeV) on the $ 16^3 \times 32 $ lattice ($ L \sim 2 $ fm) with…

High Energy Physics - Lattice · Physics 2011-01-14 Yu-Chih Chen , Ting-Wai Chiu , Tian-Shin Guu , Tung-Han Hsieh , Chao-Hsi Huang , Yao-Yuan Mao

I report low energy results on the study of fermion masses and mixing for quarks and leptons, including neutrinos within a SU(3) flavor symmetry model, where ordinary heavy fermions, top and bottom quarks and tau lepton become massive at…

High Energy Physics - Phenomenology · Physics 2012-12-20 Albino Hernandez-Galeana