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Legendre scalarization in gravity and cosmology
European Physical Journal C: Particles and Fields, 2023 We propose a new formulation of f(R) gravity, dubbed scalarized f(R) gravity, in which the Legendre transform is included as a dynamical term. This leads to a theory with second-order field equations that describes general relativity with a self ...
Spiros Cotsakis +2 more
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Metric-affine f(R) theories of gravity [PDF]
Annals of Physics, 2007 General Relativity assumes that spacetime is fully described by the metric alone. An alternative is the so called Palatini formalism where the metric and the connections are taken as independent quantities. The metric-affine theory of gravity has attracted considerable attention recently, since it was shown that within this framework some cosmological ...
THOMAS P. SOTIRIOU, Liberati, Stefano
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Consequences of $$f(R)$$ f ( R ) theories of gravity on gravitational leptogenesis [PDF]
General Relativity and Gravitation, 2013 f(R)-theories of gravity are reviewed in the framework of the matter-antimatter asymmetry in the Universe. The asymmetry is generated by the gravitational coupling of heavy (Majorana) neutrinos with the Ricci scalar curvature. In order that the mechanism works, a time varying non-zero Ricci curvature is necessary.
LAMBIASE, Gaetano +2 more
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Kinematics and dynamics off(R) theories of gravity [PDF]
General Relativity and Gravitation, 1996 13 pages, latex, to appear in ...
Rippl, Steve +3 more
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Viability of Noether Symmetry of F(R) Theory of Gravity [PDF]
International Journal of Theoretical Physics, 2012 Canonization of F(R) theory of gravity to explore Noether symmetry is performed treating R - 6(\frac{\ddot a}{a} + \frac{\dot a^2}{a^2} + \frac{k}{a^2}) = 0 as a constraint of the theory in Robertson-Walker space-time, which implies that R is taken as an auxiliary variable.
Sarkar, Kaushik +3 more
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The contribution Hans Adolph Buchdahl f(R) gravity [PDF]
EPJ Web of ConferencesHans Adolph Buchdahl was born in Mainz, Germany, into a Jewish family. He was an Australian physicist, and he was born on 7 July 1919 and died on 7 January 2010. He worked on general relativity, thermodynamics, and optics.
Lazarov Nenad Dj.
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Asymptotically flat vacuum solution in modified theory of Einstein’s gravity
European Physical Journal C: Particles and Fields, 2019 A number of recent observations have suggested that the Einstein’s theory of general relativity may not be the ultimate theory of gravity. The f(R) gravity model with R being the scalar curvature turns out to be one of the best bet to surpass the general
Surajit Kalita, Banibrata Mukhopadhyay
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Higher-derivative f(R,□R,T) theories of gravity [PDF]
International Journal of Modern Physics D, 2017 In literature, there is a model of modified gravity in which the matter Lagrangian is coupled to the geometry via trace of the stress–energy–momentum tensor [Formula: see text]. This type of modified gravity is denoted [Formula: see text] in which [Formula: see text] is Ricci scalar [Formula: see text].
Houndjo, M. J. S. +4 more
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The philosophy behind quantum gravity [PDF]
, 2006 This paper investigates some of the philosophical and conceptual issues raised by the search for a quantum theory of gravity. It is critically discussed whether such a theory is necessary in the first place, and how much would be accomplished if it is ...
Zinkernagel, Henrik +2 more
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Generalised nonminimally gravity-matter coupled theory
European Physical Journal C: Particles and Fields, 2018 In this paper, a new generalised gravity-matter coupled theory of gravity is presented. This theory is constructed by assuming an action with an arbitrary function $$f(T,B,L_m)$$ f(T,B,Lm) which depends on the scalar torsion T, the boundary term $$B ...
Sebastian Bahamonde
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