Nicola Pinamonti

Quantum states on inflationary cosmological models and their Hadamard property


During this talk we shall discuss the construction of certain quantum states for massive or massless Klein Gordon fields on some special Robertson Walker spacetime. We shall restrict our attention to the spacetimes that are used to model the early time universe in inflationary theories, namely those that at the beginning of the ``cosmological time'' looks like an expanding de Sitter spacetime. Since all of them have a common horizon we shall make use of this common geometric structure in order to encode the quantum observable as well as to construct the quantum states in the spacetime itself. We shall discuss the short distance behavior of these states and their microlocal spectral condition in particular. Finally some comments about their relation with the anisotropies of the cosmic microwave background radiation will be given.