  The first-order loop quantum gravity correction of the simplest, classical
general-relativistic Friedmann Hamiltonian constraint, emerging from a
holomorphic spinfoam cosmological model peaked on homogeneous, isotropic
geometries, is studied. The quantum Hamiltonian constraint, satisfied by the
EPRL transition amplitude between the boundary cosmological coherent states,
includes a contribution of the order of the Planck constant $\hbar$ that also
appears in the corresponding semiclassical symplectic model. The analysis of
this term gives a quantum-gravitational correction to the classical Friedmann
dynamics of the scale factor yielding a small decelerating expansion (small
accelerating contraction) of the universe. The robustness of the physical
interpretation is established for arbitrary refinements of the boundary graphs.
Also, mathematical equivalences between the semiclassical cosmological model
and certain classical fluid and scalar field theories are explored.
