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The Baryon Acoustic Oscillations (BAOs) or baryon wiggles which are present in the galaxy power spectrum at scales 100-150Mpc/h are powerful features with which to constrain cosmology. The potential of these probes is such that these are…

In this paper, we investigate the freezing quintessence scenario in late-time cosmic expansion using a non-linear $f(R, L_m)$ gravity model, $f(R,L_m)=\frac{R}{2}+L_m^\alpha$, where $\alpha$ is a free parameter. We consider a solution for…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-17 Yerlan Myrzakulov , M. Koussour , A. Caliskan , E. Güdekli , S. Muminov , J. Rayimbaev

A new kind of evolution for cyclic models in which the Hubble parameter oscillates and keeps positive has been explored in a specific $f(R,T)$ gravity reconstruction. A singularity-free cyclic universe with negative varying cosmological…

General Relativity and Quantum Cosmology · Physics 2019-02-11 Nasr Ahmed , Sultan Z. Alamri

We determine a constraint on the growth factor by measuring the damping of the baryon acoustic oscillations in the matter power spectrum using the Sloan Digital Sky Survey luminous red galaxy sample. The damping of the BAO is detected at…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-24 Gen Nakamura , Gert Huetsi , Takahiro Sato , Kazuhiro Yamamoto

The extended Galileon models possess tracker solutions with de Sitter attractors along which the dark energy equation of state is constant during the matter-dominated epoch, i.e. w_DE = -1-s, where s is a positive constant. Even with this…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-19 Antonio De Felice , Shinji Tsujikawa

In this study, we use late-time probes, such as well-localized fast radio bursts (FRBs), baryon acoustic oscillations (BAO), supernovae (SNe), and cosmic chronometers (CC) to constrain cosmological parameters through a model-independent…

We discuss various types of exotic (non-standard) singularities in the Universe: a Big-Rip (BR or type I), a Sudden Future Singularity (SFS or type II), a Generalized Sudden Future Singularity, a Finite Scale Factor singularity (FSF or type…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mariusz P. Dabrowski , Tomasz Denkiewicz

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra

Fractional cosmology modifies the standard derivative to Caputo's fractional derivative of order $\mu$, generating changes in General Relativity. Friedmann equations are modified, and the evolution of the species densities depends on $\mu$…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Miguel A. García-Aspeitia , Guillermo Fernandez-Anaya , A. Hernández-Almada , Genly Leon , Juan Magaña

We investigate the non-linear evolution of Baryon Acoustic Oscillations (BAO) in the low-redshift matter power spectrum from the DEUS-FUR $\Lambda$CDM model simulation. This is the first cosmological N-body simulation encompassing the full…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-25 Yann Rasera , Pier-Stefano Corasaniti , Jean-Michel Alimi , Vincent Bouillot , Vincent Reverdy , Irène Balmès

We investigate observational constraints on the normal branch of the warped DGP braneworld cosmology by using observational data from Type Ia Supernovae (SNIa), Baryon Acoustic Oscillations (BAO), Cosmic Microwave Background (CMB) and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 T. Azizi , M. Sadegh Movahed , Kourosh Nozari

Recent theoretical ideas and observational claims suggest that the fine structure constant alpha may be variable. We examine a spectrum of models in which alpha is a function of a scalar field. Specifically, we consider three scenarios:…

High Energy Physics - Phenomenology · Physics 2009-11-10 Charles L. Steinhardt

We investigate the cosmological evolution in a new modified teleparallel theory, called $f(T,B)$ gravity, which is formulated by connecting both $f(T)$ and $f(R)$ theories with a boundary term $B$. Here, $T$ is the torsion scalar in…

General Physics · Physics 2018-11-14 M. Zubair , Saira Waheed , M. Atif Fayyaz , Iftikhar Ahmad

We derive strong observational limits on any possible large-scale spatial variation in the values of physical 'constants' whose space-time evolution is driven by a scalar field. The limits are imposed by the isotropy of the microwave…

Astrophysics · Physics 2009-11-10 John D. Barrow

In the framework of a phenomenological cosmological model with the assumption of $\rho_{X} \propto \rho_{m} a^{\xi}$ ($\rho_{X}$ and $\rho_{m} $ are the energy densities of dark energy and matter, respectively.), we intend to diagnose the…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-28 Jie Zheng , Yun Chen , Tengpeng Xu , Zong-Hong Zhu

We present a realistic scenario of tracking of scalar fields with varying equation of state. The astrophysical constraints on the evolution of scalar fields in the physical universe are discussed. The nucleosynthesis and the galaxy…

Astrophysics · Physics 2011-07-19 Vinod B. Johri

We have shown that the varying physical constant model is consistent with the recently published variational approach wherein Einstein equations are modified to include the variation of the speed of light c, gravitational constant G and…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-21 Rajendra P. Gupta

In this work we use a template method to extract the scale associated with the Baryon Acoustic Oscillation (BAO) signal in 21cm neutral hydrogen intensity maps. We then forecast the constraints on the standard deviations of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-10 Benjamin Ostergaard , André Alencar da Costa , Yu Sang

The AdS/CFT correspondence allows us to map a dynamical cosmology to a dual quantum field theory living on the boundary of spacetime. Specifically, we study a five-dimensional model cosmology in type IIB supergravity, where the dual theory…

High Energy Physics - Theory · Physics 2013-05-30 Ben Craps , Thomas Hertog , Neil Turok

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas