  One of the methods used to extend two-dimensional bosonization to four
space-time dimensions involves a transformation to new spatial variables so
that only one of them appears kinematically. The problem is then reduced to an
Abelian version of two-dimensional bosonization with extra ``internal''
coordinates. On a formal level, putting these internal coordinates on a finite
lattice seems to provide a well-defined prescription for calculating
correlation functions. However, in the infinite-lattice or continuum limits,
certain difficulties appear that require very delicate specification of all of
the many limiting procedures involved in the construction.

High Energy Physics - Theory