Post-inflationary phases stiffer than radiation and Palatini formulation
Sign Up to like & getrecommendations! Published in 2019 at "Classical and Quantum Gravity"
DOI: 10.1088/1361-6382/ab52a8
Abstract: If the inflaton and the quintessence fields are identified, the background geometry evolves through a stiff epoch undershooting the expansion rate of a radiation-dominated plasma. For some classes of inflationary potentials this scenario is at… read more here.
Keywords: palatini; inflationary phases; post inflationary; palatini formulation ... See more keywords
Wormholes in generalized hybrid metric-Palatini gravity obeying the matter null energy condition everywhere
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DOI: 10.1103/physrevd.98.064054
Abstract: Wormhole solutions in a generalized hybrid metric-Palatini matter theory, given by a gravitational Lagrangian $f\left(R,\cal{R}\right)$, where $R$ is the metric Ricci scalar, and $\mathcal{R}$ is a Palatini scalar curvature defined in terms of an independent… read more here.
Keywords: null energy; matter; palatini; generalized hybrid ... See more keywords
Global monopole in Palatini f(R) gravity
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DOI: 10.1103/physrevd.99.064053
Abstract: We consider the space-time metric generated by a global monopole in an extension of General Relativity (GR) of the form $f(\mathcal{R})=\mathcal{R}-\lambda \mathcal{R}^2$. The theory is formulated in the metric-affine (or Palatini) formalism and exact analytical… read more here.
Keywords: global monopole; monopole palatini; palatini gravity; palatini ... See more keywords
Palatini f(R,Lm,RμνTμν) gravity and its Born-Infeld semblance
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DOI: 10.1103/physrevd.99.124027
Abstract: We investigate Palatini $f(\mathcal{R},\mathcal{L}_m, \mathcal{R}_{\mu\nu}T^{\mu\nu})$ modified theories of gravity wherein the metric and affine connection are treated as independent dynamical fields and the gravitational Lagrangian is made a function of the Ricci scalar $\mathcal{R}$, the… read more here.
Keywords: mathcal mathcal; field equations; gravity; palatini ... See more keywords
Spherically Symmetric Black Holes and Wormholes in Hybrid Metric-Palatini Gravity
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DOI: 10.1134/s0202289319040030
Abstract: The so-called hybrid metric-Palatini theory of gravity (HMPG), proposed in 2012 by T. Harko et al., is known to successfully describe both local (solar-system) and cosmological observations. This paper gives a complete description of static,… read more here.
Keywords: theory; metric palatini; scalar tensor; hybrid metric ... See more keywords