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Related papers: Finslerian perturbation for the $\Lambda$CDM model

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The paper contributes to the important and urgent problem to extend the physical theory of space-time in a Finsler-type way under the assumption that the isotropy of space is violated by a single geometrically distinguished spatial…

General Mathematics · Mathematics 2015-12-09 G. S. Asanov

We investigate the properties of a real scalar field in the Finslerian Randers spacetime, where the local Lorentz violation is driven by a geometrical background vector. We propose a dynamics for the scalar field by a minimal coupling of…

High Energy Physics - Theory · Physics 2017-01-17 J. E. G. Silva , R. V. Maluf , C. A. S. Almeida

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

We present a phenomenological model for the nature in the Finsler and Randers space-time geometries. We show that the parity-odd light speed anisotropy perpendicular to the gravitational equipotential surfaces encodes the deviation from the…

General Relativity and Quantum Cosmology · Physics 2013-02-06 Qasem Exirifard

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

The data of the Bullet Cluster 1E0657-558 released on November 15, 2006 reveal that the strong and weak gravitational lensing convergence $\kappa$-map has an $8\sigma$ offset from the $\Sigma$-map. The observed $\Sigma$-map is a direct…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-05 Zhe Chang , Ming-Hua Li , Hai-Nan Lin , Xin Li

We suggest that the vacuum field equation in Finsler spacetime is equivalent to vanishing of Ricci scalar. Schwarzschild metric can be deduced from a solution of our field equation if the spacetime preserve spherical symmetry. Supposing…

General Physics · Physics 2018-05-11 Xin Li , Zhe Chang

In this work, we study a direction dependent power spectrum in anisotropic Finsler space-time. We use this direction dependent power spectrum to address the low-l power observed in WMAP and PLANCK data. The angular power spectrum of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Zhe Chang , Pranati K. Rath , Yu Sang , Dong Zhao

There have been vigorous research attempts to test various modified gravity theories by usingphysics of the cosmic microwave background (CMB). Meanwhile, symmetry breaking such as Higgsmechanism is one of the most important phenomena in…

General Relativity and Quantum Cosmology · Physics 2020-07-01 Jiwon Park , Tae Hoon Lee

In modified gravity theories, the gravitational waves propagation are presented in nonstandard ways. We consider a friction term different from GR and constrain the modified gravitational waves propagation from observations. The modified…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-12 Jun Li

Although cosmological observations suggest that the fluctuations of seed fields are almost Gaussian, the possibility of a small deviation of their fields from Gaussianity is widely discussed. Theoretically, there exist numerous inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Maresuke Shiraishi

We consider $f\left(R\right) $-gravity in a Friedmann-Lema\^itre-Robertson-Walker spacetime with zero spatial curvature. We apply the Killing tensors of the minisuperspace in order to specify the functional form of $f\left(R\right) $ and…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Andronikos Paliathanasis

We examine the cosmological correlators induced by the simultaneous breaking of parity and of statistical isotropy, e.g., in presence of the coupling ${\cal L} = f(\phi) ( - \frac{1}{4} F^2 + \frac{\gamma}{4} F \tilde{F} )$ between the…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-28 Nicola Bartolo , Sabino Matarrese , Marco Peloso , Maresuke Shiraishi

It is proposed that if quantum states of space-time are coherent on null surfaces, holographic Planck-scale fluctuations of inflationary horizons dominate the formation of primordial scalar curvature perturbations. It is shown that the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Craig Hogan

Recently, Kostelecky [V.A. Kostelecky, Phys. Lett. B 701, 137 (2011)] proposed that the spontaneous Lorentz invariance violation (sLIV) is related to Finsler geometry. Finsler spacetime is intrinsically anisotropic and induces naturally…

High Energy Physics - Phenomenology · Physics 2012-10-15 Zhe Chang , Sai Wang

As a prototypical massive field theory we study the scalar field on the recently introduced Finsler spacetimes. We show that particle excitations exist that propagate faster than the speed of light recognized as the boundary velocity of…

General Relativity and Quantum Cosmology · Physics 2012-05-23 Christian Pfeifer , Mattias N. R. Wohlfarth

We present a fully covariant and gauge-invariant calculation of the evolution of anisotropies in the cosmic microwave background (CMB) radiation. We use the physically appealing covariant approach to cosmological perturbations, which…

Astrophysics · Physics 2008-11-26 Anthony Challinor , Anthony Lasenby

We propose a new model of cosmology based on an anisotropic background and a specific $f(R)$ theory of gravity. It is shown that field equations of $f(R)$ gravity in a Bianchi type I background give rise to a modified Friedmann equation.…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Cemsinan Deliduman , Oguzhan Kasikci , Vildan Keles Tugyanoglu

Ricci scalar being zero is equivalent to the vacuum field equation in Finsler space-time. The Schwarzschild metric can be concluded from the field equation's solution if the space-time conserves spherical symmetry. This research aims to…

General Relativity and Quantum Cosmology · Physics 2024-04-25 Z. Nekouee , S. K. Narasimhamurthy , S. K. J. Pacif

The question of whether unobserved short-wavelength modes of the gravitational field can induce decoherence in the long-wavelength modes (``the decoherence of spacetime'') is addressed using a simplified model of perturbative general…

General Relativity and Quantum Cosmology · Physics 2009-10-28 John T. Whelan
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