Entanglement entropy in FRW backgrounds

We use holography in order to study the entanglement entropy for a spherical entangling surface FRW background with an arbitrary time dependence of scale factor. The calculation is done various dimensions, allowing nonzero spatial curvature. CFT at temperature this also considered. Our approach based on coordinate transformations that relate extremization problem one static background, careful determination UV cutoff. demonstrate agreement expected form and known results specific cases. In four apart from cutoff-dependent terms, we compute discuss finite term related expansion rate.