Angular Momentum Mixing in Single Flavor Color Superconductivity with Transverse Pairing

Because of the equal strength of the pairing potential mediated by one-gluon exchange for all partial waves to the leading order QCD running coupling constant and the nonlinearity of the gap equation, the non-spherical pairing in single flavor color superconductivity(CSC) can not be restricted in a single non-s-wave channel and the mixing among different angular momenta will occur. In this paper, we examine the angular momentum mixing in single flavor CSC with transverse pairing, in which the pairing quarks have opposite helicity. We find that the free energy of all non-spherical pairing states are lowered by angular momentum mixing compared with that contain p-wave only. But the amount of the free energy drop is numerically small. Consequently the most stable pairing state that respect the time reversal invariance remains the spherical CSL.Comment: 16 pages, 2 figures, 1 table in Revte

Leptonic Charm Decays

We review the recent experimental results on D and Ds meson leptonic decays from CLEO-c, Belle, and BABAR, which results in the decay constants f_D= (206.7 +- 8.9) MeV and f_Ds= (257.3 +- 5.3) MeV. The latter is an average obtained by the Heavy Flavor Averaging Group (HFAG). Comparisons with Lattice QCD (LQCD) calculations are discussed.Comment: Proceedings of CKM2010, the 6th International Workshop on the CKM Unitarity Triangle, University of Warwick, UK, 6-10 September 201

The Time Invariance Principle, Ecological (Non)Chaos, and A Fundamental Pitfall of Discrete Modeling

This paper is to show that most discrete models used for population dynamics in ecology are inherently pathological that their predications cannot be independently verified by experiments because they violate a fundamental principle of physics. The result is used to tackle an on-going controversy regarding ecological chaos. Another implication of the result is that all continuous dynamical systems must be modeled by differential equations. As a result it suggests that researches based on discrete modeling must be closely scrutinized and the teaching of calculus and differential equations must be emphasized for students of biology

The imaginary part of the gap function in color superconductivity

We clarify general properties of the energy gap regarding its functional dependence on the energy-momentum dictated by the invariance under a space inversion or a time reversal. Then we derive perturbatively the equation of the imaginary part of the gap function for dense QCD in weak coupling and generalize our results from 2SC case to CFL case. We confirm that the imaginary part is down by $g$ relative to the real part in weak coupling. The numerical results show that, up to the leading order, the imaginary part is no larger than one MeV at extremely large densities and can be as large as several MeV the densities are of physical interest.Comment: 15 pages, 2 figures, typos corrected, a figure replaced. The version to be appeared in Nucl.Phys.