  We investigate the structure of two point functions for the QFT dual to an
asymptotically Lorentzian AdS-wormhole. The bulk geometry is a solution of
5-dimensional second order Einstein Gauss Bonnet gravity and causally connects
two asymptotically AdS space times. We revisit the GKPW prescription for
computing two-point correlation functions for dual QFT operators O in
Lorentzian signature and we propose to express the bulk fields in terms of the
independent boundary values phi_0^\pm at each of the two asymptotic AdS
regions, along the way we exhibit how the ambiguity of normalizable modes in
the bulk, related to initial and final states, show up in the computations. The
independent boundary values are interpreted as sources for dual operators O^\pm
and we argue that, apart from the possibility of entanglement, there exists a
coupling between the degrees of freedom leaving at each boundary. The AdS_(1+1)
geometry is also discussed in view of its similar boundary structure. Based on
the analysis, we propose a very simple geometric criterium to distinguish
coupling from entanglement effects among the two set of degrees of freedom
associated to each of the disconnected parts of the boundary.
