  We analyze the phase space of gravity non-minimally coupled to a scalar field
in a generic local Lorentz frame. We reduce the set of constraints to a
first-class one by fixing a specific hypersurfaces in the phase space. The main
issue of our analysis is to extend the features of the vacuum case to the
presence of scalar matter by recovering the emergence of an SU(2) gauge
structure and the non-dynamical role of boost variables. Within this scheme,
the super-momentum and the super-Hamiltonian are those ones associated with a
scalar field minimally coupled to the metric in the Einstein frame. Hence, the
kinematical Hilbert space is defined as in canonical Loop Quantum Gravity with
a scalar field, but the differences in the area spectrum are outlined to be the
same as in the time-gauge approach.
