  The worldsheet formulation is introduced for lattice gauge theories with
dynamical fermions. The partition function of lattice compact QED with
staggered fermions is expressed as a sum over surfaces with border on
self-avoiding fermionic paths. The surfaces correspond to the world sheets of
loop-like pure electric flux excitations and meson-like configurations (open
electric flux tubes carrying matter fields at their ends). The proposed
formulation does not have the problem of the additional doubling of the fermion
species due to the discretization of time. The gauge non-redundancy and the
geometric transparency are two appealing features of this description. From the
computational point of view, the partition function involves fewer degrees of
freedom than the Kogut-Susskind formulation and offers an alternative and more
economic framework to perform numerical computations with dynamical fermions.
