Massive SU Research Articles

Separation of variables and vacuum structure of N = 2 SUSY QCD

We show how the method of separation of variables can be used to construct integrable models corresponding to curves describing vacuum structure of four-dimensional N = 2 SUSY Yang-Mills theories. We use this technique to construct models corresponding to SU( N) Yang-Mills theory with N f < 2 N matter hypermultiplets by generalising the periodic Toda lattice. We also show that some special cases of massive SU(3) gauge theory can be equivalently described by the generalisations of the Goryachev-Chaplygin top obtained via separation of variables.

Strongly coupled massive QCD3 and frustrated Heisenberg antiferromagnets: fractional statistics and chiral-spin order

Strongly coupled massive SU(NC) and U(NC) QCD3 on a lattice is studied using the 1/NC expansion. The quark mass terms have a definite sign in the present model, and therefore the system explicitly breaks the parity symmetry. The continuum counterpart generates the Maxwell + Chern-Simons theory by integrating out the quark field. In the present paper, we shall integrate out the gauge fields using the strong-coupling expansion and obtain a frustrated quantum Heisenberg model as an effective model. The ground state of the above effective quantum spin model is studied using the large-NC approximation. There are two phases; one is a Neel-ordered state and the other is a state with a chiral-spin order. It is explicitly shown that the chiral-spin ordered state corresponds to a state with spontaneous generation of color magnetic flux in the original theory and fractional statistics appears in that phase. This result strongly suggests that there are (at least) two phases in the massive QCD3 and Maxwell-CS theory. One is the confinement phase and the other is the perturbative deconfinement phase with fractional-statistics excitations.

Complex static solutions and wave solutions to (2+1)-dimensional topologically massive gauge theories

Complex static solutions with zero action and zero energy-momentum tensor are constructed for the (2+1)-dimensional topologically massive SU(2) gauge theory by generalizing the vortex-like solutions. These solutions can be treated as real gauge potentials for the noncompact gauge group SL(2, C ). Wave solutions are also exhibited.

Baryon number generation in a flipped SU(5) × U(1) model

We consider the possibilities for generating a baryon asymmetry in the early universe in a flipped SU(5) × U(1) model inspired by the superstring. Depending on the temperature of the radiation background after inflation we can distinguish between two scenarios for baryogenesis: (1) after reheating the original SU(5) × U(1) symmetry is restored, or there was no inflation at all; (2) reheating after inflation is rather weak and SU(5) × U(1) is broken. In either case the asymmetry is generated by the out-of-equilibrium decays of a massive SU(3) × SU(2) × U(1) singlet field φm. In the flipped SU(5) × U(1) model, gauge symmetry breaking is triggered by strong coupling phenomena, and is in general accompanied by the production of entropy. We examine constraints on the reheating temperature and the strong coupling scale in each of the scenarios.

The H-dibaryon in hidden gauge theory

Classical solutions in SU(3) v hidden gauge theory are investigated. Unstable SO(3) solutions in the B=2 and B=4 sectors converge towards saddle points of a massive SU(3). The H-dibaryon corresponds to the lowest-lying SO(3) solution. Its properties are calculated and the problem of quantization is discussed.

Extended solutions of an SU(2) gauge theory with fermions.

This paper explores the idea that there can exist interesting classical solutions to non-Abelian gauge theories which represent extended systems. These solutions provide possible alternative starting points for perturbative quantum field theories. For the particular case of an SU(2) gauge theory with spherical symmetry, we find a simple example of a ``vacuum'' solution with a nonvanishing chiral order parameter: \ensuremath{\chi}=\ensuremath{\psi}\ifmmode\bar\else\textasciimacron\fi{}\ensuremath{\psi}. We also find a simple set of spinors representing systems of massive SU(2) fermions in the field of a Wu-Yang monopole.

Cranking in hedgehog models with vector mesons

A cranking calculation is performed in a massive SU(2) × SU(2) × U(1) model with valence quarks and the σ, π, ϱ, A and ω mesons. The nucleon moment of inertia, the N-Δ mass splitting and the proton and neutron charge distributions are obtained. The general framework and the specific ansatz for the cranked fields can be used in any hedgehog model with vector mesons. A possible role of η and δ mesons is also discussed.

Topologically massive chromodynamics in the perturbative regime.

Topologically massive SU(N) gauge theories are studied by using the loop expansion in the Landau gauge. Ward identities for infinitesimal and topologically nontrivial gauge transformations are derived, and checked to one-loop order. The renormalized propagators and vertices are shown to be well behaved about zero momentum to arbitrary order in perturbation theory. We also establish that only massive states contribute to the discontinuities of physical amplitudes.

Diagonalizability of the longitudinal sector of the functional integral in massive SU (2) Yang–Mills theories via topological contributions

The problem of longitudinal sector diagonalizability of the functional integral in massive SU (2) Yang–Mills theories is revisited. A new decomposition law of a massive SU (2) vector field into transverse and longitudinal parts is proposed which takes into account the more recently discovered topological properties of SU (2) gauge theories. After establishing the credibility of this decomposition law, it is shown how it leads to the diagonalizability of the longitudinal sector of the functional integral. This result is related to the problem of the existence of the zero-mass limit in massive SU (2) Yang–Mills theories.

Factorization in the massive SU( N) thirring model

We study various massive SU( N) Thirring models including the broken chiral model in the 1/ N-expansion. We show that the S-matrix factorizes when the renormalized coupling constant for the scalar and the chiral interaction is fixed at a special value.