• Publications
  • Influence
Healthy theories beyond Horndeski
Jérôme Gleyzes, 2 David Langlois, Federico Piazza, 4 and Filippo Vernizzi CEA, Institut de Physique Théorique, F-91191 Gif-sur-Yvette cédex, CNRS, Unité de recherche associée-2306, F-91191Expand
Exploring gravitational theories beyond Horndeski
We have recently proposed a new class of gravitational scalar-tensor theories free from Ostrogradski instabilities, in arXiv:1404.6495. As they generalize Horndeski theories, or "generalized"Expand
Essential Building Blocks of Dark Energy
We propose a minimal description of single field dark energy/modified gravity within the effective field theory formalism for cosmological perturbations, which encompasses most existing models. WeExpand
The effective field theory of dark energy
We propose a universal description of dark energy and modified gravity that includes all single-field models. By extending a formalism previously applied to inflation, we consider the metricExpand
Violations of the equivalence principle in a dilaton-runaway scenario
We explore a version of the cosmological dilaton-fixing and decoupling mech- anism in which the dilaton-dependence of the low-energy effective action is extremized for infinitely large values of theExpand
Runaway dilaton and equivalence principle violations.
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 amplitude of densityExpand
Spontaneous symmetry probing
A bstractFor relativistic quantum field theories, we consider Lorentz breaking, spatially homogeneous field configurations or states that evolve in time along a symmetry direction. We dub thisExpand
Rapidly-Varying Speed of Sound, Scale Invariance and Non-Gaussian Signatures
We show that curvature perturbations acquire a scale invariant spectrum for any constant equation of state, provided the fluid has a suitably time-dependent sound speed. In order for modes to exitExpand
Zoology of condensed matter: framids, ordinary stuff, extra-ordinary stuff
A bstractWe classify condensed matter systems in terms of the spacetime symmetries they spontaneously break. In particular, we characterize condensed matter itself as any state in aExpand
More on gapped Goldstones at finite density: more gapped Goldstones
A bstractIt was recently argued that certain relativistic theories at finite density can exhibit an unconventional spectrum of Goldstone excitations, with gapped Goldstones whose gap is exactlyExpand