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A Bayesian statistical analysis using redshift space distortions data is performed to test a model of Symmetric Teleparallel Gravity where gravity is non-metrical. The cosmological background mimics a $\Lambda$CDM evolution but differences…

General Relativity and Quantum Cosmology · Physics 2020-06-15 Bruno J. Barros , Tiago Barreiro , Tomi Koivisto , Nelson J. Nunes

The detailed nature of dark energy remains a mystery, leaving the possibility that its effects might be explained by changes to the laws of gravity on large scales. The peculiar velocities of galaxies directly trace the strength of gravity…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-29 Stuart Lyall , Chris Blake , Ryan J. Turner

Classical generalization of general relativity is considered as gravitational alternative for unified description of the early-time inflation with late-time cosmic acceleration. The structure and cosmological properties of number of…

General Relativity and Quantum Cosmology · Physics 2011-07-26 Shin'ichi Nojiri , Sergei D. Odintsov

We develop a robust data fusion algorithm for field reconstruction of multiple physical phenomena. The contribution of this paper is twofold: First, we demonstrate how multi-spatial fields which can have any marginal distributions and…

Methodology · Statistics 2019-06-11 Pengfei Zhang , Gareth W. Peters , Ido Nevat , Keng Boon Teo , Yixin Wang

We compare void size and clustering statistics for nDGP and $f(R)$ gravity models and GR using N-body simulations. We show how it is critical to consider the statistics derived from mock galaxy catalogs rather than the dark matter halos…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Christopher Wilson , Rachel Bean

The field equations in modified gravity theories possess an important decoupling property with respect to certain classes of nonholonomic frames. This allows us to construct generic off--diagonal solutions depending on all spacetime…

General Relativity and Quantum Cosmology · Physics 2015-02-23 Sergiu I. Vacaru

Distance measurements are currently the most powerful tool to study the expansion history of the universe without specifying its matter content nor any theory of gravitation. Assuming only an isotropic, homogeneous and flat universe, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-02 S. D. P. Vitenti , M. Penna-Lima

We study the cosmology of a specific class of nonlocal model of modified gravity, the so-called Deser-Woodard (DW) model, modifying the Einstein-Hilbert action by a term $\sim R f(\Box^{-1}R)$, where $f$ is a free function. Choosing $f$ so…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-18 Luca Amendola , Yves Dirian , Henrik Nersisyan , Sohyun Park

We consider a class of modified gravity models where the terms added to the standard Einstein-Hilbert Lagrangian are just a function of the metric only. For linearized perturbations around an isotropic space-time, this class of models is…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Richard A. Battye , Jonathan A. Pearson

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 paper, we have considered gravity in a 5-dimensional warped product space-time with a time-dependent warp factor, time-dependent extra dimension and a bulk cosmological constant. The braneworld is described by a spatially flat…

General Relativity and Quantum Cosmology · Physics 2010-05-19 Sarbari Guha , Pinaki Bhattacharya

The expansion of the Universe is accelerated as testified by observations of SNeIa at varying redshifts. Explanations of this acceleration are of two kinds: modifications of Einstein gravity or new forms of energy. An example of modified…

Astrophysics · Physics 2011-11-10 M. Roos

We apply the Union2 compilation of 557 supernova Ia data, the baryon acoustic oscillation measurement of distance, the cosmic microwave background radiation data from the seven year Wilkinson Microwave Anisotropy Probe, and the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-27 Yungui Gong , Xiao-ming Zhu , Zong-Hong Zhu

In this paper, three kinds of simple parameterized deceleration parameters $q(z)=a+\frac{b z}{1+z}$, $q(z)=a+\frac{b z}{(1+z)^2}$ and $q(z)={1/2}+\frac{a z+b}{(1+z)^2}$ are reconstructed from the latest Sne Ia Gold dataset, observational…

Astrophysics · Physics 2009-11-13 Lixin Xu , Chengwu Zhang , Baorong Chang , Hongya Liu

Using a model-independent Gaussian process (GP) method to reconstruct the dimensionless luminosity distance $D$ and its derivatives, we derive the evolution of the dimensionless Hubble parameter $E$, the deceleration parameter $q$, and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-03 Xue Zhang , Yin-Hao Xu , Yu Sang

In modern cosmology, the discovery of the universe's accelerated expansion has significantly transformed our understanding of cosmic evolution and expansion history. The unknown properties of dark energy, the driver of this acceleration,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Xincheng Zhu , Rui Xu , Dandan Xu

We have used publicly available kinematic data for the S2 star to constrain the parameter space of MOdified Gravity. Integrating geodesics and using a Markov Chain Monte Carlo algorithm we have provided with the first constraint on the…

General Relativity and Quantum Cosmology · Physics 2022-06-28 Riccardo Della Monica , Ivan de Martino , Mariafelicia de Laurentis

We constrain the expansion history of the Universe and the cosmological matter density fraction in a model-independent way by exclusively making use of the relationship between background and perturbations under a minimal set of…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 Jaime Ruiz-Zapatero , Carlos García-García , David Alonso , Pedro G. Ferreira , Richard D. P. Grumitt

The normal branch of Dvali-Gabadadze-Porrati braneworld gravity with brane tension is confronted by the currently available cosmic observations from the geometrical and dynamical perspectives. On the geometrical side, the type Ia supernova…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-28 Lixin Xu
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