ar X iv : h ep - t h / 04 02 14 8 v 1 1 9 Fe b 20 04 Surveillance on the light - front gauge fixing

ar X iv : h ep - p h / 04 02 19 0 v 1 1 8 Fe b 20 04 1 Pentaquarks in the 10 F - and 10 F - plets

ar X iv : h ep - t h / 04 02 14 3 v 1 1 8 Fe b 20 04 Gauge Symmetry Breaking : Higgs - less Mass Generation and Radiation Phenomena

Gauge symmetries generally appear as a constraint algebra, under which one expects all physical states to be singlets. However, quantum anomalies and boundary conditions introduce central charges and change this picture, thus causing gauge/diffeomorphism modes to become physical. We expose a cohomological (Higgs-less) generation of mass in U (N)-gauge invariant Yang-Mills theories through non-t...

ar X iv : h ep - p h / 04 02 19 6 v 1 1 8 Fe b 20 04 The 2 - particle irreducible effective action in gauge theories

The goal of this paper is to develop the formalism of the two-particle irreducible (2PI) [1] (or Cornwall Jackiw Tomboulis (CJT) [2]) effective action (EA) in a way appropiate to its application to non equilibrium gauge theories. We hope this review article will stimulate new work into this field.

ar X iv : h ep - p h / 04 02 23 9 v 1 2 3 Fe b 20 04 The η → π 0 π 0 γγ decay in Generalized χ PT

Calculations of η → ππγγ decay in Generalized chiral perturbation theory are presented. Tree level and next-to-leading corrections are involved. Sensitivity to violation of the Standard counting is discussed.

ar X iv : h ep - p h / 04 02 29 2 v 1 2 7 Fe b 20 04 1 SU ( 3 ) Chiral Effective Field

A personal overview on the present status of SU(3) chiral perturbation theory in the baryonic sector is given. Recent developments are presented and remaining challenges are pointed out.