Weak-coupling analysis of chiral gauge theories on a lattice

Abstract
We formulate a chiral gauge-invariant theory of lattice fermions by introducing extra degrees of freedom. It is applied to the chiral U(1) gauge theories in two and four dimensions, and the effective actions of the gauge fields are calculated which indicate the mass generation of the gauge bosons. However, the difficulty is pointed out to execute the perturbation with a finite gauge-boson mass.