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The current paper reports an investigation of the cosmological implications of symmetric teleparallel gravity within a modified $f(Q)$ theory. We construct a specific exponential $f(Q)$ model as $f(Q) = Q + \eta_1 Q_0\left(1 - e^{-\eta_2…

广义相对论与量子宇宙学 · 物理学 2025-11-11 Sanjeeda Sultanaa , Surajit Chattopadhyay

Higher order theories of gravity have recently attracted a lot of interest as alternative candidates to explain the observed cosmic acceleration without the need of introducing any scalar field. A critical ingredient is the choice of the…

天体物理学 · 物理学 2009-11-10 S. Capozziello , V. F. Cardone , A. Troisi

Cosmography is an ideal tool to investigate the cosmic expansion history of the Universe in a model-independent way. The equations of motion in modified theories of gravity are usually very complicated; cosmography may select practical…

广义相对论与量子宇宙学 · 物理学 2021-01-04 Sanjay Mandal , Deng Wang , P. K. Sahoo

In this paper, we use genetic algorithms, a specific machine learning technique, to achieve a model-independent reconstruction of $f(T)$ gravity. By using $H(z)$ data derived from cosmic chronometers and radial Baryon Acoustic Oscillation…

宇宙学与河外天体物理 · 物理学 2025-06-09 Redouane El Ouardi , Amine Bouali , Imad El Bojaddaini , Ahmed Errahmani , Taoufik Ouali

Cosmographic approach, a Taylor expansion of the Hubble function, has been used as a model-independent method to investigate the evolution of the universe in the presence of cosmological data. Apart from possible technical problems like the…

宇宙学与河外天体物理 · 物理学 2022-01-04 Ahmad Mehrabi , Mehdi Rezaei

The current accelerated expansion of the Universe remains ones of the most intriguing topics in modern cosmology, driving the search for innovative statistical techniques. Recent advancements in machine learning have significantly enhanced…

宇宙学与河外天体物理 · 物理学 2025-01-03 José de Jesús Velázquez , Luis A. Escamilla , Purba Mukherjee , J. Alberto Vázquez

Over the last years some interest has been gathered by $f(Q)$ theories, which are new candidates to replace Einstein's prescription for gravity. The non-metricity tensor $Q$ allows to put forward the assumption of a free torsionless…

宇宙学与河外天体物理 · 物理学 2021-03-17 Ismael Ayuso , Ruth Lazkoz , Vincenzo Salzano

Several models based on General Relativity and Modified Gravity aim to reproduce the observed universe with precision comparable to the flat-$\Lambda$CDM cosmological model. In this study, we investigate the consistency of some of these…

宇宙学与河外天体物理 · 物理学 2025-12-05 Fernanda Oliveira , Bruno Ribeiro , Wiliam S. Hipólito-Ricaldi , Felipe Avila , Armando Bernui

We perform a model-independent investigation of the thermodynamic evolution of the Universe by reconstructing the expansion history from observational data using Gaussian Process regression. We consider three independent combinations of…

宇宙学与河外天体物理 · 物理学 2026-04-22 Afaq Maqsood , Tanima Duary

This paper examines the late-time accelerating Universe and the formation of large-scale structures within the modified symmetric teleparallel gravity framework, specifically using the $f(Q)$-gravity model, in light of recent cosmological…

广义相对论与量子宇宙学 · 物理学 2024-12-31 Shambel Sahlu , Amare Abebe

Extended teleparallel gravity, characterized by $F(Q)$ function where $Q$ is the non-metricity scalar, is one of the most promising approaches to general relativity. In this paper, we reexamine a specific dynamical dark energy model, which…

广义相对论与量子宇宙学 · 物理学 2024-08-14 Omar Enkhili , Safae Dahmani , Dalale Mhamdi , Taoufik Ouali , Ahmed Errahmani

We use dynamical system methods to explore the general behaviour of $f(T)$ cosmology. In contrast to the standard applications of dynamical analysis, we present a way to transform the equations into a one-dimensional autonomous system,…

广义相对论与量子宇宙学 · 物理学 2018-03-14 A. Awad , W. El Hanafy , G. G. L. Nashed , Emmanuel N. Saridakis

We apply two methods, namely the Gaussian processes and the non-parametric smoothing procedure, to reconstruct the Hubble parameter $H(z)$ as a function of redshift from 15 measurements of the expansion rate obtained from age estimates of…

宇宙学与河外天体物理 · 物理学 2016-03-02 Zhengxiang Li , J. E. Gonzalez , Hongwei Yu , Zong-Hong Zhu , J. S. Alcaniz

In this study, we explore the cosmological evolution of the Universe in the framework of covariant $f(Q)$ gravity, with a coupling function that evolves dynamically in proportion to the Hubble parameter. Two specific forms of the function…

广义相对论与量子宇宙学 · 物理学 2026-04-29 S. A. Narawade , S. A. Kadam

In this paper, we present a cosmological model within the framework of symmetric teleparallel gravity, focusing on $f(Q)$ gravity, where $Q$ represents the non-metricity scalar. Utilizing cosmological datasets, we derive an accelerating…

广义相对论与量子宇宙学 · 物理学 2024-08-09 S. A. Narawade , S. H. Shekh , B. Mishra , Wompherdeiki Khyllep , Jibitesh Dutta

We study observational constraints on the cosmographic functions up to the fourth derivative of the scale factor with respect to cosmic time, i.e., the so-called snap function, using the non-parametric method of Gaussian Processes. As…

宇宙学与河外天体物理 · 物理学 2022-05-18 A. M. Velasquez-Toribio , J. C. Fabris

Direct observations of the Hubble rate, from cosmic chronometers and the radial baryon acoustic oscillation scale, can out-perform supernovae observations in understanding the expansion history, because supernovae observations need to be…

宇宙学与河外天体物理 · 物理学 2012-10-26 Marina Seikel , Sahba Yahya , Roy Maartens , Chris Clarkson

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their…

宇宙学与河外天体物理 · 物理学 2020-04-22 Marco Raveri

Recent cosmological observations have achieved high-precision measurements of the Universe's expansion history, prompting the use of nonparametric methods such as Gaussian processes (GP) regression. We apply GP regression for reconstructing…

宇宙学与河外天体物理 · 物理学 2025-11-21 Jia-yan Jiang , Kang Jiao , Tong-Jie Zhang

We explore the role of the affine connection in $f(Q)$ gravity, a modified theory where gravity is governed by non-metricity within the symmetric teleparallel framework. Although the connection is constrained to be flat and torsionless, it…

广义相对论与量子宇宙学 · 物理学 2025-11-27 Ismael Ayuso , Mariam Bouhmadi-López , Che-Yu Chen , Xiao Yan Chew , Konstantinos Dialektopoulos , Yen Chin Ong