Hai-cang Ren

Chromomagnetic instability and the LOFF state in a two flavor color superconductor

We explore the relation between the chromomagnetic instability of a homogeneous two flavor color superconductor and the LOFF state. We perturb the free energy of the 2SC by generating a small net momentum for the quark pair. We find that the imaginary Meissner mass of a particular gluon implies that the LOFF state is energetically favored.

Possible higher order correction to the chiral vortical conductivity in a gauge field plasma

The two-loop contributions to the chiral vortical conductivity are considered. The Kubo formula together with the anomalous Ward identity of the axial vector current suggest that there may be a nonzero correction to the coefficient of the

The Meissner effect in a two flavor LOFF color superconductor

{T}^{2}

Ginzburg-Landau free energy functional of color superconductivity at weak coupling

term of the conductivity.

Some field theoretic issues regarding the chiral magnetic effect

Abstract We calculate the magnetic polarization tensor of the photon and of the gluons in a two flavor color superconductor with a LOFF pairing that consists of a single plane wave. We show that at zero temperature and within the range of the values of the Fermi sea displacement that favors the LOFF state, all the eigenvalues of the magnetic polarization tensor are non-negative. Therefore the chromomagnetic instabilities pertaining to a gapless color superconductor disappear.

Linearized analysis of the Dvali–Gabadadze–Porrati brane model

We derive the Ginzburg-Landau free energy functional of color superconductivity in terms of the thermal diagrams of QCD in its perturbative region. The zero mode of the quadratic term coefficient yields the same transition temperature, including the preexponential factor, as the one obtained previously from the Fredholm determinant of the two-quark scattering amplitude. All coefficients of the free energy can be made identical to those of a BCS model by setting the Fermi velocity of the latter equal to the speed of light. We also calculate the induced symmetric color condensate near

A neutral two-flavor LOFF color superconductor

{T}_{c}

The finite ’t Hooft coupling correction on the jet quenching parameter in a \mathcal{N}=4 super Yang-Mills plasma

and find that it scales as the cubic power of the dominant antisymmetric color component. We show that in the presence of an inhomogeneity and a nonzero gauge potential, while the color-flavor locked condensate dominates in the bulk, the unlocked condensate, the octet, emerges as a result of a simultaneous color-flavor rotation in the core region of a vortex filament or at the junction of super and normal phases.

Gauge field fluctuations and first-order phase transition in color superconductivity.

In this paper, we shall address some field theoretic issues regarding the chiral magnetic effect. The general structure of the chiral magnetic current consistent with the electromagnetic gauge invariance is obtained and the impact of the infrared divergence is examined. Some subtleties on the relation between the chiral magnetic effect and the axial anomaly are clarified through a careful examination of the infrared limit of the relevant thermal diagrams.

Magnetic and inverse magnetic catalysis in the Bose-Einstein condensation of neutral bound pairs

Abstract We solve the Einstein equations in the Dvali–Gabadadze–Porrati model with a static, spherically symmetric matter distribution on the physical brane and obtain an exact expression for the gravitational field outside the source to the first order in the gravitational coupling. Although, this expression when confined on the physical brane reproduces the correct 4− D Newtonian potential for distances r s ⪡ r ⪡ λ , where λ is a characteristic length scale of the model, it does not coincide with the standard linearized form of the 4− D Schwarzschild metric. The solution reproduces the 5− D Schwarzschild metric in the linearized approximation for r ⪢ λ .