A new approach to scalar-tensor theories

par Julio Fabris (UFES, Vitoria, Brazil)

jeudi 2 juin 2016, 11:00 → 12:00 Europe/Paris

Auditorium (Annecy-le-Vieux)

The scalar-tensor theories have been since long time an alternative to the General Relativity theory. However, the observational constraints, either at cosmological or local levels, reduce these theories to configurations very near to the GR ones. The possibility to obtain important new effects at cosmological level, keeping untouched the success at local level, can be obtained by using screening mechanisms. A different approach, which can open new possibilities, can be implemented by considering the scalar field as an external field, not subjected to the variational principle. We discuss this new approach in the cosmological context. Other possible framework incorporating somehow quantum effects at classical level are also discussed.