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Related papers: Structure formation in $f(T)$ gravity and a soluti…

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We study the effect of global topology of the spatial geometry on the cosmic microwave background (CMB) for closed flat and closed hyperbolic models in which the spatial hypersurface is multiply connected. If the CMB temperature…

Astrophysics · Physics 2013-09-06 Kaiki Taro Inoue

An $f(R)$ gravity model is proposed to realize a late time accelerated expansion of our Universe. To test the viability of an $f(R)$ gravity model through cosmic observations, the background evolution and the Einstein-Boltzmann equation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Lixin Xu

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

Being based on the only assumption that the universe is homogenous and isotropic on large scales, cosmography is an ideal tool to investigate the cosmic expansion history in a almost model-independent way. Fitting the data on the luminosity…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-10 S. Capozziello , V. F. Cardone , H. Farajollahi , A. Ravanpak

The Hubble Constant measured from the anisotropy in the cosmic microwave background (CMB) is shown to be independent of small changes from the standard model of the redshift dependence of dark energy. Modifications of the Friedmann equation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jeremy Mould

We study the evolution of density perturbations for a class of $f(R)$ models which closely mimic $\Lambda$CDM background cosmology. Using the quasi-static approximation, and the fact that these models are equivalent to scalar-tensor…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Stephen A Appleby , Jochen Weller

A complete perturbation theory suitable for teleparallel gravity is developed. The proposed perturbation scheme takes into account perturbations of the coframe, the metric, and the spin-connection, while ensuring that the resulting…

General Relativity and Quantum Cosmology · Physics 2023-05-16 Alexandre Landry , Robert J. van den Hoogen

We investigate the exponential $f(Q)$ symmetric teleparallel gravitation, namely $f(Q)=Q+\alpha Q_0(1-e^{-\beta\sqrt{Q/Q_0}})$ using \texttt{ME-GADGET} code to probe the structure formation with box sizes $L_{\mathrm{box}}=10/100$ Mpc$/h$…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-18 Oleksii Sokoliuk , Simran Arora , Subhrat Praharaj , Alexander Baransky , P. K. Sahoo

In this work we present a further investigation about Teleparallel Gravity Cosmology. We demonstrate that according the current astrophysical data (CC+Pantheon+BAO samplers with late universe measurements SH0ES+H0LiCOW), an $f(T,B)$ theory…

General Relativity and Quantum Cosmology · Physics 2021-05-07 Celia Escamilla-Rivera , Jackson Levi Said

In the present study, we consider an extended form of teleparallel Lagrangian $f(T,\phi,X)$, as function of a scalar field $\phi$, its kinetic term $X$ and the torsion scalar $T$. We use linear perturbations to obtain the equation of matter…

General Relativity and Quantum Cosmology · Physics 2018-05-09 Habib Abedi , Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

General theory of relativity can be equivalently formulated on a flat space-time associating a torsion-free affine connection of non-vanishing non-metricity scalar $Q$. In this paper, we present an extension of this, viz., the $f(Q)$ theory…

General Relativity and Quantum Cosmology · Physics 2024-11-04 Avik De , Dalia Saha , Ganesh Subramaniam , Abhik Kumar Sanyal

Anisotropies in the cosmic microwave background radiation due to gravity waves are investigated. An initial spectrum of gravity waves may have been induced during an epoch of inflation. We study the propagation of such a spectrum in a…

Astrophysics · Physics 2008-02-03 Ruth Durrer , Tina Kahniashvili

We investigate exact solutions and the asymptotic dynamics for the Friedmann-Lema\^{\i}tre-Robertson-Walker universe with nonzero spatial curvature in the fourth-order modified teleparallel gravitational theory known as $f\left( T, B\right)…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Andronikos Paliathanasis , Genly Leon

It is shown that teleparallel $F(T)$ theories of gravity combined with holonomy corrected Loop Quantum Cosmology (LQC) support a Matter Bounce Scenario (MBS) which is a potential alternative to the inflationary paradigm. The Matter Bounce…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Jaume Haro , Jaume Amorós

We present an all-sky formalism for the Cosmic Microwave Background (CMB) bispectrum induced by the primordial non-Gaussianities not only in scalar but also in vector and tensor fluctuations. We find that the bispectrum can be formed in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

We study the late-time cosmological expansion of a modified teleparallel gravity model of type logarithmic type. This modified gravitational lagrangian yields a cosmological constant term and also power-law corrections to the teleparallel…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Adriel O. Aquino , Euclides G. Silva

Symmetric teleparallel gravity theories, in which the gravitational interaction is attributed to the nonmetricity of a flat, symmetric, but not metric-compatible affine connection, have been a topic of growing interest in recent studies.…

General Relativity and Quantum Cosmology · Physics 2022-01-03 Manuel Hohmann

We develop the effective field theory approach to torsional modified gravities, a formalism that allows for the systematic investigation of the background and perturbation levels separately. Starting from the usual effective field theory…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Chunlong Li , Yong Cai , Yi-Fu Cai , Emmanuel N. Saridakis

One way to account for the acceleration of the universe is to modify general relativity, rather than introducing dark energy. Typically, such modifications introduce new degrees of freedom. It is interesting to consider models with no new…

Astrophysics · Physics 2011-05-12 Sean M. Carroll , Ignacy Sawicki , Alessandra Silvestri , Mark Trodden

We propose a new class of $f(R)$ theory where its Weyl gauge symmetry is broken in the primordial era of the universe. This symmetry forces one to adopt a new scalar field, namely a Weyl field and a gauge vector boson. Furthermore, an…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Jiwon Park , Tae Hoon Lee
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