  The interaction of quantum light with matter like that inside a cavity is
known to give rise to mixed light-matter states called polaritons. We discuss
the impact of rotation of the cavity on the polaritons. It is shown that the
number of polaritons increases due to this rotation. The structure of the
original polaritons is modified and new ones are induced by the rotation that
strongly depend on the angular velocity and the choice of axis of rotation. In
molecules the rotation can change the number of light-induced conical
intersections and their dimensionality and hence strongly impact their quantum
dynamics. General consequences are discussed.
