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Related papers: Quantitative constraints on modified gravity parad…

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We present a rigorous theoretical and observational analysis of the Hybrid $ f(Q) $ class of models by including the late-time modifying $ 1/Q $ term. After deriving strict viability conditions from the analytical expansion history, we show…

General Relativity and Quantum Cosmology · Physics 2026-04-15 Ameya Kolhatkar , P. K. Sahoo

The key probes of the growth of large-scale structure are its rate $f$ and amplitude $\sigma_8$. Redshift space distortions in the galaxy power spectrum allow us to measure only the combination $f\sigma_8$, which can be used to constrain…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Louis Perenon , Stéphane Ilić , Roy Maartens , Alvaro de la Cruz-Dombriz

This study investigates the accelerated cosmic expansion within the Ho\v{r}ava-Lifshitz Model. To constrain the cosmological parameters of this model, we incorporate 17 Baryon Acoustic Oscillation points, 31 Cosmic Chronometer points, 40…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-16 Himanshu Chaudhary , Ujjal Debnath , Shibesh Kumar Jas Pacif , Niyaz Uddin Molla , G. Mustafa , S. K. Maurya

The negative pressure accompanying gravitationally-induced particle creation can lead to a cold dark matter (CDM) dominated, accelerating Universe (Lima et al. 1996) without requiring the presence of dark energy or a cosmological constant.…

Astrophysics · Physics 2009-07-22 G. Steigman , R. C. Santos , J. A. S. Lima

In this study, we consider three dark energy models in which $\Lambda$ is not constant, but has a dynamic nature that depends on the Hubble parameter $H$ and/or its time derivative $\dot{H}$. We analyze the generalized running vacuum model,…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Christine R. Farrugia , Joseph Sultana , Jurgen Mifsud

We analyze the science reach of a next generation galaxy redshift survey such as BigBOSS to fit simultaneously for time varying dark energy equation of state and time- and scale-dependent gravity. The simultaneous fit avoids potential bias…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-06 Scott F. Daniel , Eric V. Linder

It has been widely shown that the cosmological parameters and dark energy can be constrained by using data from type-Ia supernovae (SNe Ia), the cosmic microwave background (CMB) anisotropy, the baryon acoustic oscillation (BAO) peak from…

Astrophysics · Physics 2009-06-23 F. Y. Wang , Z. G. Dai , Zong-Hong Zhu

The thermodynamics-gravity conjecture reveals that one can derive the gravitational field equations by using the first law of thermodynamics and vice versa. Considering the entropy associated with the horizon in the form of non-extensive…

General Relativity and Quantum Cosmology · Physics 2021-11-04 Mahnaz Asghari , Ahmad Sheykhi

Cosmography can be considered as a sort of a model-independent approach to tackle the dark energy/modified gravity problem. In this review, the success and the shortcomings of the $\Lambda$CDM model, based on General Relativity and standard…

General Relativity and Quantum Cosmology · Physics 2019-04-09 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

We review current observations of the homogeneous cosmological expansion which, because they measure only kinematic variables, cannot determine the dynamics driving the recent accelerated expansion. The minimal fit to the data, the flat…

Astrophysics · Physics 2015-05-13 Sidney Bludman

In this paper we present conjoined constraints on several cosmological models from the expansion history $H(z)$ and cosmic growth $f\sigma_8(z)$. The models we study include the CPL $w_0w_a$ parametrization, the Holographic Dark Energy…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-27 Spyros Basilakos , Savvas Nesseris

Assuming that the Universe at higher redshifts (z \sim 4 and beyond) is consistent with LCDM model as constrained by the Planck measurements, we reanalyze the low redshift cosmological data to reconstruct the Hubble parameter as a function…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-18 Koushik Dutta , Ruchika , Anirban Roy , Anjan A. Sen , M. M. Sheikh-Jabbari

We develop a formalism to characterize the redshift evolution of the dark energy potential. Our formalism makes use of quantities similar to the Horizon-flow parameters in inflation and is general enough that can deal with multiscalar…

Astrophysics · Physics 2008-11-26 Joan Simon , Licia Verde , Raul Jimenez

In this study, we investigate the cosmological history within the framework of modified $f(Q)$ gravity, which proposes an alternative theory of gravity where the gravitational force is described by a non-metricity scalar. By employing a…

General Relativity and Quantum Cosmology · Physics 2023-08-30 N. Myrzakulov , M. Koussour , A. Mussatayeva

In the context of the Relativistic Quantum Geometry formalism, where the cosmological constant is promoted to a dynamical variable by attributing it a geometric interpretation as a result of a flux on the boundary of a manifold and…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Juan Ignacio Musmarra , Claudia Moreno , Rafael Hernández-Jiménez

We explore the phenomenological consequences of general late-time modifications of gravity in the quasi-static approximation, in the case where cold dark matter is non-minimally coupled to the gravitational sector. Assuming spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 Jérôme Gleyzes , David Langlois , Michele Mancarella , Filippo Vernizzi

The current paper provides a comprehensive examination of a dark energy cosmological model in the classical regime, in which a generic scalar field is regarded as a dark energy source. Einstein's field equations are solved in model…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Ritika Nagpal , Shibesh Kumar Jas Pacif , Abhishek Parida

Viable models of modified gravity designed to produce cosmic acceleration at the current epoch, closely mimic the $\Lambda$CDM model at the level of background cosmology. However, this degeneracy is generically broken at the level of linear…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Alessandra Silvestri

In this work, two models of metric $f(R)$ gravity in the Jordan frame are investigated as a dynamical description of the late-time cosmic expansion using binned Type Ia Supernovae data. The aim is to provide an explanation for the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-15 A. Valletta , G. Montani , M. G. Dainotti , E. Fazzari

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…

Astrophysics · Physics 2009-03-12 Alan Cooney , Simon DeDeo , Dimitrios Psaltis
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