  A fruitful avenue in investigating out-of-equilibrium quantum many-body
systems is to abruptly change their Hamiltonian and study the subsequent
evolution of their quantum state. If this is done once, the setup is called a
quench, while if it is done periodically, it is called Floquet driving. We
consider the solvable setup of a two-dimensional CFT driven by Hamiltonians
built out of conformal symmetry generators: in this case, the quantum dynamics
can be understood using two-dimensional geometry. We investigate how the
dynamics is reflected in the holographic dual three-dimensional spacetime and
find new horizons. We argue that bulk operators behind the new horizons are
reconstructable by virtue of modular flow.
