Dark Energy and Its Interactions with Neutrinos

In this talk I will firstly review on the current constraints on the equation of state of the dark energy from observational data, then present a new scenario of dark energy dubbed Quintom. The recent fits to the type Ia supernova data and the cosmic microwave background and so on in the literature find that the behavior of dark energy is to great extent in consistency with a cosmological constant, however the dynamical dark energy scenarios are generally not ruled out, and one class of models with an equation of state transiting from below -1 to above -1 as the redshift increases is mildly favored. The second part of the talk is on interacting dark energy. I will review briefly on the models of neutrino dark energy