  By using Wilsonian Renormalization Group (RG) methods we rigorously establish
the existence of a Weyl semimetallic phase in an interacting three dimensional
fermionic lattice system, by showing that the zero temperature Schwinger
functions are asymptotically close to the ones of massless Dirac fermions. This
is done via an expansion which is convergent in a region of parameters, which
includes the quantum critical point discriminating between the semimetallic and
the insulating phase.
