  In holographic duality, if a boundary state has a geometric description that
realizes the Ryu-Takayanagi proposal then its entanglement entropies must obey
certain inequalities that together define the so-called holographic entropy
cone. A large family of such inequalities have been proven under the assumption
that the bulk geometry is static, using a method involving contraction maps. By
using kinematic space techniques, we show that in two boundary (three bulk)
dimensions, all entropy inequalities that can be proven in the static case by
contraction maps must also hold in holographic states with time dependence.
