  In this note, we investigate some simple generalizations of a bottom-up
holographic approach to cosmology introduced in arXiv:1810.10601. Our models
utilize the Karch/Randall/Takayanagi ansatz for the gravitational dual of a
boundary conformal field theory, involving pure AdS gravity and an
end-of-the-world brane. Following a suggestion made in arXiv:2102.05057, we
consider models with an additional interface brane in the bulk. We find that
solutions with a viable cosmological interpretation exist only if our model is
further generalized, for example by including an Einstein-Hilbert term in the
ETW brane action. The physical validity of such models is discussed from the
perspective of the effective theory.
