Tufts/CfA/MIT Cosmology Seminar, at Tufts: Thibault Damour, IHES Title: Gravitational-strength scalars and Cosmology Abstract: String theory abounds with light scalar fields having gravitational-strength couplings (the dilaton and various moduli). These fields a priori create a host of observational problems in low-energy gravitational physics and cosmology. Mechanisms for solving these problems, and their observable consequences, notably in cosmology, will be discussed.