  We analyze whether a pair of neutral two level atoms can become entangled in
a finite time while they remain causally disconnected. The interaction with the
e. m. field is treated perturbatively in the electric dipole approximation. We
start from an initial vacuum state and obtain the final atomic correlations for
the cases where n = 0, 1, or 2 photons are produced in a time t, and also when
the final field state is unknown. Our results show that correlations are
sizable inside and outside the mutual light cone for n= 1 and 2, and also that
quantum correlations become classical by tracing over the field state. For n =
0 we obtain entanglement generation by photon propagation between the atoms,
the correlations come from the indistinguishability of the source for n = 1,
and may give rise to entanglement swapping for n = 2.
