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We consider a dynamic scenario for characterizing the late Universe evolution, aiming to mitigate the Hubble tension. Specifically, we consider a metric $f(R)$ gravity in the Jordan frame which is implemented to the dynamics of a flat…

General Relativity and Quantum Cosmology · Physics 2024-08-06 Giovanni Montani , Nakia Carlevaro , Mariaveronica De Angelis

We propose a model for modified gravity that meets the conditions of viability. The model has stable constant curvature solution and for an special case contains flat space time solution. The model also leads to matter stability under small…

General Relativity and Quantum Cosmology · Physics 2015-06-22 L. N. Granda

In the present work, we review some general aspects of modified gravity theories, investigating mathematical and physical properties and, more specifically, the feature of viable and realistic models able to reproduce the dark energy epoch…

General Relativity and Quantum Cosmology · Physics 2013-10-16 Ratbay Myrzakulov , Lorenzo Sebastiani , Sergio Zerbini

Standard cosmological data analyses typically constrain simple phenomenological dark-energy parameters, for example the present-day value of the equation of state parameter, $w_0$, and its variation with scale factor, $w_a$. However,…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 Yuewei Wen , Eva Nesbit , Dragan Huterer , Scott Watson

In this work, we obtain measurements of the Hubble constant in the context of modified gravity theories. We set up our theoretical framework by considering viable cosmological $f(R)$ and $f(T)$ models, and we analyzed them through the use…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-07 Rocco D'Agostino , Rafael C. Nunes

In a modified gravity theory, the propagation equation of gravitational waves will be presented in a non-standard way. Therefore this tenor mode perturbation of time-space, as a complement to the scalar mode perturbation, provides a unique…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Lixin Xu

The reconstruction scheme is developed for modified $f(R)$ gravity with realistic matter (dark matter, baryons, radiation). Two versions of such theory are constructed: the first one describes the sequence of radiation and matter…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent…

General Physics · Physics 2012-11-13 Jhumpa Bhadra , Ujjal Debnath

In this paper we analyze a suite of cosmological simulations of modified gravitational action f(R) models, where cosmic acceleration is induced by a scalar field that acts as a fifth force on all forms of matter. In particular, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-23 Héctor Gil-Marín , Fabian Schmidt , Wayne Hu , Raul Jimenez , Licia Verde

In our companion paper we identified a complete set of manifestly gauge-invariant observables for general relativity. This was possible by coupling the system of gravity and matter to pressureless dust which plays the role of a dynamically…

General Relativity and Quantum Cosmology · Physics 2010-02-17 K. Giesel , S. Hofmann , T. Thiemann , O. Winkler

By considering linear-order departures from general relativity, we compute a novel expression for the weak lensing convergence power spectrum under alternative theories of gravity. This comprises an integral over a 'kernel' of general…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-22 C. Danielle Leonard , Tessa Baker , Pedro G. Ferreira

The time delay in gravitational lenses can be used to derive the Hubble constant in a relatively simple way. The results of this method are less dependent on astrophysical assumptions than in many other methods. The most important…

Astrophysics · Physics 2007-05-23 Olaf Wucknitz

We study the linear and nonlinear structure formation in the dilaton and symmetron models of modified gravity using a generic parameterisation which describes a large class of scenarios using only a few parameters, such as the coupling…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Philippe Brax , Anne-Christine Davis , Baojiu Li , Hans A. Winther , Gong-Bo Zhao

The huge amounts of undetected and exotic dark matter and dark energy needed to make general relativity work on large scales argue that we should investigate modifications of gravity. The only stable, metric-based and invariant alternative…

General Relativity and Quantum Cosmology · Physics 2018-07-06 R. P. Woodard

Over the last decades, tests on the standard model of cosmology, the so-called $\Lambda$CDM model, have been widely analysed and compared with many different models for describing dark energy. Modified gravities have played an important…

General Relativity and Quantum Cosmology · Physics 2024-12-13 Sergei D. Odintsov , Diego Sáez-Chillón Gómez , German S. Sharov

Recently, in [1], we presented the first combined non-parametric reconstruction of the three time-dependent functions that capture departures from the standard cosmological model, $\Lambda$CDM, in the expansion history and gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Marco Raveri , Levon Pogosian , Matteo Martinelli , Kazuya Koyama , Alessandra Silvestri , Gong-Bo Zhao

One of the primary limiting sources of systematic uncertainty in forthcoming weak lensing measurements is systematic uncertainty in the quantitative relationship between the distortions due to gravitational lensing and the measurable…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-10 Eric Huff , Rachel Mandelbaum

We present a concise description of the basic features of gravity-matter models based on the formalism of non-canonical spacetime volume-forms in its two versions: the method of non-Riemannian volume-forms (metric-independent covariant…

General Relativity and Quantum Cosmology · Physics 2019-10-15 David Benisty , Eduardo Guendelman , Alexander Kaganovich , Emil Nissimov , Svetlana Pacheva

Self-consistent ${\it N}$-body simulations of modified gravity models are a key ingredient to obtain rigorous constraints on deviations from General Relativity using large-scale structure observations. This paper provides the first detailed…

As cosmology rapidly approaches the data-dominated phase of stage IV large scale structure surveys, the modelling of nonlinear scales has become a serious challenge that faces the community, particularly when analysing models beyond $w$CDM.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Sankarshana Srinivasan , Shreya Prabhu , Kai Lehman , Ajiv Krishnan V. , Jochen Weller
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