Extended Theories of Gravity with Generalized Energy Conditions

Abstract

We address the problem of the energy conditions in modified gravity taking into account the additional degrees of freedom related to scalar fields and curvature invariants. The latter are usually interpreted as generalized {\it geometrical fluids} that differ in meaning with respect to the matter fluids generally considered as sources of the field equations. In extended gravity theories the curvature terms are encapsulated in a tensor $H^{ab}$ and a coupling $g({\Psi }^i)$ that can be recast as effective Einstein field equations, with corrections to the energy-momentum tensor of matter. The formal validity of standard energy inequalities does not assure basic requirements such as the attractive nature of gravity, so we argue that the energy conditions have to be considered in a wider sense.

arXiv commentSumbitted to the Proceedings of the Spanish Relativity Meeting- ERE2014"Amost 100 years after Einstein revolution", to appear in the Journal of Physics: Conference Series

References in corpus (34)

• Extended Theories of Gravity
• Introduction to Modified Gravity and Gravitational Alternative for Dark Energy
• f(R,T) gravity
• Modified gravity with negative and positive powers of the curvature: unification of the inflation and of the cosmic acceleration
• Metric-Affine Gauge Theory of Gravity: Field Equations, Noether Identities, World Spinors, and Breaking of Dilation Invariance
• Curvature Quintessence
• Extra force in $f(R)$ modified theories of gravity
• Extended Theories of Gravity and their Cosmological and Astrophysical Applications
• The Cosmology of Generalized Modified Gravity Models
• f(R,L_m) gravity
• On Physical Equivalence between Nonlinear Gravity Theories
• Low surface brightness galaxies rotation curves in the low energy limit of $R^n$ gravity : no need for dark matter?
• Where new gravitational physics comes from: M-theory?
• 1/R Curvature Corrections as the Source of the Cosmological Acceleration
• Modified-gravity wormholes without exotic matter
• f(R, T, R_μνT^μν) gravity phenomenology and ΛCDM universe
• Further matters in space-time geometry: $f(R,T,R_{\mu \nu }{T}^{\mu \nu })$ gravity
• Energy conditions in f(R)-gravity
• Dark energy and dark matter as curvature effects
• Dark matter as a geometric effect in f(R) gravity
• Metric-Palatini gravity unifying local constraints and late-time cosmic acceleration
• Generalized energy conditions in Extended Theories of Gravity
• Energy conditions in modified gravity
• Analysis of Rotation Curves in the framework of R^n gravity
• Cosmology of hybrid metric-Palatini f(X)-gravity
• Energy conditions in modified Gauss-Bonnet gravity
• The virial theorem and the dark matter problem in hybrid metric-Palatini gravity
• Generalized virial theorem in f(R) gravity
• Hybrid modified gravity unifying local tests, galactic dynamics and late-time cosmic acceleration
• Dark matter and dark energy as a effects of Modified Gravity
• Anisotropic Scalar-Tensor Cosmologies
• Conformally related metrics and Lagrangians and their physical interpretation in cosmology
• Generalized dark gravity
• Lectures on Mathematical Cosmology

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• Stability criterion for white dwarfs in Palatini $f(R)$ gravity
• On stability of a neutron star system in Palatini gravity
• Polytropic stars in Palatini gravity
• Energy conditions in Starobinsky supergravity
• Invariant quantities of Scalar-Tensor Theories for stellar structure
• On the existence of static spherically-symmetric objects in action-dependent Lagrangian theories
• Kinetic gravity braiding wormhole geometries
• Eckart heat-flux applicability in $F(\Phi ,X)R$ theories and the existence of temperature gradients
• Galactic dynamics in the presence of scalaron: A perspective from $\mathbf{f}(\mathbf{R})$ gravity
• Extended Theories of Gravity in cosmological and astrophysical applications