Conformal frames in cosmology

Abstract

From higher dimensional theories, e.g. string theory, one expects the presence of non-minimally coupled scalar fields. We review the notion of conformal frames in cosmology and emphasize their physical equivalence, which holds at least at a classical level. Furthermore, if there is a field, or fields, which dominates the universe, as it is often the case in cosmology, we can use such notion of frames to treat our system, matter and gravity, as two different sectors. On one hand, the gravity sector which describes the dynamics of the geometry and on the other hand the matter sector which has such geometry as a playground. We use this interpretation to build a model where the fact that a curvaton couples to a particular frame metric could leave an imprint in the CMB.

Plenary talk given at the 2nd LeCosPA Symposium: Everything about Gravity

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Cited by in corpus (18)

• Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution
• Constant-roll Inflation in $F(R)$ Gravity
• Inflationary $\alpha$-attractors from $F(R)$ Gravity
• Precision Predictions for the Primordial Power Spectra from f(R) Models of Inflation
• Inflationary Attractors in $F(R)$ Gravity
• Invariant slow-roll parameters in scalar-tensor theories
• Meaning of the field dependence of the renormalization scale in Higgs inflation
• Field redefinitions in theories beyond Einstein gravity using the language of differential forms
• On the Trans-Planckian Censorship Conjecture and the Generalized Non-Minimal Coupling
• Slow-Roll Inflation in the Jordan Frame
• Gravitational collapse of massless scalar field in $f(R)$ gravity
• Cosmology in Minkowski space
• The role of conformal symmetry in gravity and the standard model
• Quantum simulation of dark energy candidates
• Attractor Cosmology from non-minimally Coupled Gravity
• Exploring the self-tuning of the cosmological constant from Planck mass variation
• Energy momentum tensor of a non-minimally coupled scalar from the equivalence of the Einstein and Jordan frames
• Conformal invariant cosmological perturbations via the covariant approach: multicomponent universe