Dynamical vacuum energy in the expanding Universe

The study of the dark energy is a central subject in cosmology and fundamental physics. Despite the many efforts, our theoretical understanding of the ultimate nature of the dark energy component of the universe still lags well behind the astounding experimental evidence achieved from the increasingly sophisticated observational tools at our disposal. While the canonical possibility is a strict cosmological constant, the exceeding simplicity of this possibility lies also at the root of its unconvincing theoretical status. In this work the student will have the opportunity to explore the cosmological implications of the dynamical models of the vacuum energy. Some of these models are actually well-motivated from the theoretical point of view (e.g. within quantum field theory in curved spacetime) and may provide a rich phenomenology that could be explored in future observations. In particular, the dynamics of vacuum can affect the Hubble expansion and the details of structure formation, as collected e.g. from the data on type Ia supernovae, the Cosmic Microwave Background and the Baryonic Acoustic Oscillations. In this study the cosmology of some these models will be solved and confronted with the data. At the same time the relation of these vacuum models on possible evidence of dynamical dark energy recently pointed out in the literature will also be addressed.