arXiv subjects

Myck Schwetz

Publications and source records attributed to Myck Schwetz.

5 recordsLinked to original sources

arXiv2000

The 2+1 Dimensional NJL Model at Finite Temperature

We decribe properties of 2+1-dimensional Nambu-Jona-Lasinio (NJL) models at finite-temperature, beginning with the model with a discrete chiral symmetry. We then consider the model with a continuous $U(1) \times U(1)$ chiral symmetry, describing the restoration of the symmetry at finite temperature. In each case, we compute the free energy and comment on a recently proposed constraint based upon it. We conclude with a brief discussion of NJL models with larger chiral symmetries.

hep-ph↗

arXiv1999

On the QCD Ground State at High Density

We investigate the possible ground states of QCD at asymptotic densities, where the theory is expected to exhibit color superconductivity. We characterize the color-flavor structure of possible diquark condensates, and find those that are energy extrema by solving the weak-coupling Dyson-Schwinger equations, including Landau damping and the Meissner effect. We show that, as previously anticipated, in the two flavor case the vacuum breaks SU(3) color to SU(2) and in the three flavor case the vacua with color-flavor locking (CFL) have the lowest energy. We identify a number of relatively flat directions in the potential along which the pattern of gauge symmetry breaking changes and parity is violated. We discuss possible phenomenological consequences of our results.

hep-ph↗

arXiv1998

Lattice Tests of Supersymmetric Yang-Mills Theory?

Supersymmetric Yang Mills theory is directly accessible to lattice simulations using current methodology, and can provide a non-trivial check of recent exact results in SQCD. In order to tune the lattice simulation to the supersymmetric point it is neccessary to understand the behavior of the theory with a small supersymmetry breaking gaugino mass. We introduce a soft breaking gaugino mass in a controlled fashion using a spurion analysis. We compute the gluino condensate, vacuum energy and bound-state masses as a function of the gaugino mass, providing more readily accessible predictions which still test the supersymmetric results. Finally we discuss diagnostics for obtaining the bare lattice parameters that correspond to the supersymmetric continuum limit.

hep-th↗

arXiv1998

The Field Theory of Non-Supersymmetric Brane Configurations

We identify the 4D field theories living on the world volume of D4 branes in non-supersymmetric type IIA string theory constructions. They are softly broken N=2 SQCD with the breakings introduced through vevs of the auxilliary fields in the spurion coupling field. Exact solutions of these theories for perturbing soft breakings exist in the literature. We calculate the ratios of string tensions in softly broken N=2 SU(N) gauge theory testing the recently proposed M-theory prediction. The semi-classical result of M-theory is renormalized in the non-supersymmetric models.

hep-th↗

arXiv1997

Gaugino condensate and Veneziano-Yankielowicz effective Lagrangian

We study the sypersymmetric pure Yang-Mills theory with semisimple Lie groups. We show that the general form of the gluino condensate is determined solely by the symmetries of the theory and it is in disagreement with the recently proposed existence of a conformal phase in SYM theory. We discuss the peculiarities of the Veneziano-Yankielowicz effective Lagrangian approach and explain how it is related to the calculation of the gluino condensate

hep-th↗