Results 11 to 20 of about 167,529,233 (288)
Matter Instability in Theories with Modified Induced Gravity [PDF]
Advances in High Energy Physics, 2012 Matter stability is a necessary condition to have a cosmologically viable model. Modified gravity in the spirit of f(R) theories suffers from matter instability in some subdomains of the model parameter space.
Kourosh Nozari, Faeze Kiani
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Modified Theories of Gravity [PDF]
, 2013 The recent observational data in cosmology seem to indicate that the universe is currently expanding in an accelerated way. An intriguing interpretation of these data is that they may just be signalling that Einstein's General Relativity is not the correct description of gravity when we consider distances of the order of the present horizon of the ...
Fluvio Sbisa, F. Sbisa', Sbisa, Fulvio
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A class of minimally modified gravity theories [PDF]
Journal of Cosmology and Astroparticle Physics, 2017 We investigate the Hamiltonian structure of a class of gravitational theories whose actions are linear in the lapse function. We derive the necessary and sufficient condition for a theory in this class to have two or less local physical degrees of freedom.
Lin, Chunshan, Mukohyama, Shinji
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Thermodynamics of Modified Theories of Gravity [PDF]
, 2010 VCU Theses and ...
Hackebill, Aric
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Gravitational waves in modified teleparallel theories of gravity [PDF]
European Physical Journal C: Particles and Fields, 2018 Teleparallel theory of gravity and its modifications have been studied extensively in literature. However, gravitational waves has not been studied enough in the framework of teleparallelism.
Habib Abedi, Salvatore Capozziello
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Modified teleparallel theories of gravity [PDF]
, 2018 Teleparallel gravity is an alternative formulation of gravity which has the same field equations as General Relativity (GR), therefore, it is also known as the Teleparallel equivalent of General Relativity (TEGR).
Bahamonde, Sebastian
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ENTROPY FORCE AND SELF-GRAVITY FACTOR OF MODIFIED GRAVITY THEORIES
Modern Physics Letters A, 2011 We investigate the entropy force of modified gravity theories on trapping horizons. It is shown that if the entropy force is separated as a uniform term from the variation of entropy, the associated self-gravity factor is not the simple two in Einstein gravity but is different for various gravity theories.
Zhu, Shu, Wu, Shao-Feng, Yang, Guo-Hong
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Reflections on the Covariance of Modified Teleparallel Theories of Gravity [PDF]
Universe, 2019 We review the current status of the Lorentz covariance in teleparallel and modified teleparallel theories of gravity, and discuss the controversial features of the different approaches. We also revisit the issue of the remnant Lorentz gauge symmetries in
Cecilia Bejarano +3 more
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The viability of modified gravity theories [PDF]
, 2009 PhDThis thesis studies the viability of classes of modified gravity (MG) theories based on generalisations of the Einstein-Hilbert action. Particular emphasis is given to f(R) theories in both the metric and Palatini formalisms, scalar-tensor theories ...
Uddin, Kotub
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Maximum force in modified gravity theories [PDF]
Physical Review D, 2020 10 pages, no figures, section on power law gravity dropped, additions to conclusions, The paper is dedicated to the fond memory of one of the authors, John Barrow who passed away on 26 Sept 2020 - Naresh Dadhich ...
John D. Barrow, Naresh Dadhich
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