Ubiquitous quantum scarring does not prevent ergodicity

We discuss the connection between quantum scarring, localization in phase space, and ergodicity in the Dicke model. This model is used to describe interacting light-matter systems and has been realized with different AMO platforms. We show that all the eigenstates of the Dicke model in the chaotic region are scarred, although with different degrees of scarring and different levels of phase-space localization. We also explain that ergodicity is an ensemble property, achievable only through temporal averages. Therefore, scarring, localization and lack of ergodicity are not synonyms, although connections exist.