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Gauge Symmetry Enhancement and Radiatively Induced Mass in the Large N Nonlinear Sigma Model

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 نشر من قبل Taichi Itoh
 تاريخ النشر 2001
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We consider a hybrid of nonlinear sigma models in which two complex projective spaces are coupled with each other under a duality. We study the large N effective action in 1+1 dimensions. We find that some of the dynamically generated gauge bosons acquire radiatively induced masses which, however, vanish along the self-dual points where the two couplings characterizing each complex projective space coincide. These points correspond to the target space of the Grassmann manifold along which the gauge symmetry is enhanced, and the theory favors the non-Abelian ultraviolet fixed point.



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