Recent developments on the black hole information problem have revealed
that a unitary Page curve can be recovered from the contributions of
wormholes to the Euclidean gravitational path integral. The inclusion
of such wormholes leads to an interpretation of the path integral as
some kind of ensemble average. In this talk, I'll discuss how the
presence of these wormholes can make a contribution to the free energy
(more generally, the generating functional) of a gravitational theory,
which can be computed from the path integral via a replica trick
distinct from the more familiar one used to compute von Neumann
entropies. Focusing on the case of JT gravity, I'll sketch how this
replica trick works, and discuss difficulties with the required analytic
continuation. These difficulties parallel some qualitative features of
spin glasses including replica symmetry breaking, and I'll discuss what
light these parallels might shed on the gravitational picture.