Publications (58)
Sub-eV scalar dark matter through the super-renormalizable Higgs portal
Federico Piazza, Maxim Pospelov
The Higgs portal of the Standard Model provides the opportunity for coupling to a very light scalar field via the super-renormalizable operator . This allows…
Quantum degrees of freedom of a region of spacetime
Federico Piazza
The holographic principle and the thermodynamics of de Sitter space suggest that the total number of fundamental degrees of freedom associated with any finite-volume region of spac…
Minimal cosmography
Federico Piazza, Thomas Schucker
The minimal requirement for cosmography - a nondynamical description of the universe - is a prescription for calculating null geodesics, and timelike geodesics as a function of the…
Scalar-tensor theories, trace anomalies and the QCD-frame
Francesco Nitti, Federico Piazza
We consider the quantum effects of matter fields in scalar-tensor theories and clarify the role of trace anomaly when switching between conformally related `frames'. We exploit the…
Runaway dilaton and equivalence principle violations
Thibault Damour, Federico Piazza, Gabriele Veneziano
In a recently proposed scenario, where the dilaton decouples while cosmologically attracted towards infinite bare string coupling, its residual interactions can be related to the a…
Moving superfluids in the rotating universe
Jose Beltrán Jiménez, Federico Piazza, Javier Vecino
We study homogeneous cosmological models featuring shift-symmetric scalar fields (or, superfluids) in relative motion. In the presence of anisotropy this universe generally feature…