New class of hybrid metric-Palatini scalar-tensor theories of gravity

Abstract

A class of scalar-tensor theories (STT) including a non-metricity that unifies metric, Palatini and hybrid metric-Palatini gravitational actions with non-minimal interaction is proposed and investigated from the point of view of their consistency with generalized conformal transformations. It is shown that every such theory can be represented on-shell by a purely metric STT possessing the same solutions for a metric and a scalar field. A set of generalized invariants is also proposed. This extends the formalism previously introduced in \cite{kozak2019}. We then apply the formalism to Starobinsky model, write down the Friedmann equations for three possible cases: metric, Palatini and hybrid metric-Palatini, and compare some inflationary observables.

34 pages in LaTeX, comments and references added, final version published in JCAP

References in corpus (40)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Dark energy cosmology: the equivalent description via different theoretical models and cosmography tests
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Modified f(R) gravity consistent with realistic cosmology: from matter dominated epoch to dark energy universe
• Extended Theories of Gravity and their Cosmological and Astrophysical Applications
• Class of viable modified $f(R)$ gravities describing inflation and the onset of accelerated expansion
• Cosmological viability of f(R)-gravity as an ideal fluid and its compatibility with a matter dominated phase
• Palatini Approach to Modified Gravity: f(R) Theories and Beyond
• Modified f(R) gravity unifying R^m inflation with \LambdaCDM epoch
• Observational signatures of f(R) dark energy models that satisfy cosmological and local gravity constraints
• Solar system and equivalence principle constraints on f(R) gravity by chameleon approach
• Inflation with Non-Minimal Coupling: Metric vs. Palatini Formulations
• The (pseudo)issue of the conformal frame revisited
• Higgs inflation with loop corrections in the Palatini formulation
• Cosmology of hybrid metric-Palatini f(X)-gravity
• Physical non-equivalence of the Jordan and Einstein frames
• Density perturbations in f(R) gravity theories in metric and Palatini formalisms
• Invariant quantities in the scalar-tensor theories of gravitation
• Frame-dependence of higher-order inflationary observables in scalar-tensor theories
• Dark matter and dark energy as a effects of Modified Gravity
• Metric-affine Gravity and Inflation
• Is exponential gravity a viable description for the whole cosmological history?
• Resurrecting Quadratic Inflation with a non-minimal coupling to gravity
• Constraints on f(R) Cosmology in the Palatini Formalism
• Deceleration versus Acceleration Universe in Different Frames of $F(R)$ Gravity
• Coleman-Weinberg linear inflation: metric vs. Palatini formulation
• CMB and Matter Power Spectra of Early f(R) Cosmology in Palatini Formalism
• How (Not) to Palatini
• Inflationary Perturbations in Palatini Generalised Gravity
• Tracing the high energy theory of gravity: an introduction to Palatini inflation
• Invariant solutions and Noether symmetries in Hybrid Gravity
• Accelerated Cosmological Models in Modified Gravity tested by distant Supernovae SNIa data
• Palatini formulation of pure $R^2$ gravity yields Einstein gravity with no massless scalar
• Dynamics of Linear Perturbations in the hybrid metric-Palatini gravity
• Reconstructing the inflationary $f(R)$ from observations
• Inflation and dark energy from f(R) gravity
• Constant-roll in the Palatini-$R^2$ models
• Filtering out the cosmological constant in the Palatini formalism of modified gravity
• A new extended quintessence
• On the Emergence of Accelerating Cosmic Expansion in f(R) Theories of Gravity

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• Estimating the parameters of Hybrid Palatini gravity model with the Schwarzschild precession of S2, S38 and S55 stars: case of bulk mass distribution
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• Dynamical reconstruction of the $\Lambda$CDM model in hybrid metric-Palatini gravity
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• Scalar-tensor cosmologies in a minisuperspace formulation: a case study
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