Extended Nambu endash Jona-Lasinio model and hidden local symmetry of low energy QCD

Using the standard auxiliary field method, we derive from the extended Nambu endash Jona-Lasinio model an effective meson action containing vector and axial-vector mesons in addition to Goldstone bosons. The vector and axial-vector mesons in this effective action transform as gauge fields of hidden local symmetry Glocal=[U(n)LxU(n)R]local. Here, the realization of enlarged hidden local symmetry is accomplished via the introduction of two kinds of open-quote open-quote compensating close-quote close-quote fields. For obtaining the intrinsic-parity-violating part of the action, we generalize the standard gauged Wess-Zumino-Witten action such that it also contains two kinds of open-quote open-quote compensators close-quote close-quote in addition to the usual Goldstone bosons as well as the vector and axial-vector mesons. This generalized gauged Wess-Zumino-Witten action turns out to have GglobalxGlocal symmetry, where Gglobal is the usual U(n)LxU(n)R global chiral symmetry while Glocal is the U(n)LxU(n)R hidden local symmetry. This means that Glocal has no gauge anomaly and its associated vector and axial-vector mesons can be regarded as gauge bosons of Glocal. The introduction of the coupling with the external electroweak fields requires us to gauge some appropriate subgroup of Gglobal. To make it consistent with the anomaly structure of QCD is a nontrivial problem. We explain how this can be done, following the recent suggestion by several authors. copyright 1996 The American Physical Society