中文
相关论文

相关论文: Comprehensive Analysis of a Non-Singular Bounce in…

200 篇论文

We apply the bottom-up reconstruction technique in the context of bouncing cosmology in F(R) gravity, where the starting point is a suitable ansatz of observable quantity (like spectral index or tensor to scalar ratio) rather than a priori…

广义相对论与量子宇宙学 · 物理学 2020-09-01 S. D. Odintsov , V. K. Oikonomou , Tanmoy Paul

In this paper, we have shown the matter bounce scenario of the Universe in an extended symmetric teleparallel gravity, the f(Q) gravity. Motivated from the bouncing scenario and loop quantum cosmology (LQC), the form of the function $f(Q)$…

广义相对论与量子宇宙学 · 物理学 2023-02-06 A. S. Agrawal , B. Mishra , P. K. Agrawal

In $f(T)$ gravity, the theory modifies the gravitational action by introducing a function of the torsion scalar $T$. This approach allows for a different treatment of gravity than general relativity, particularly in cosmological contexts.…

广义相对论与量子宇宙学 · 物理学 2024-10-08 S. Davood Sadatian , S. Mohamad Reza Hosseini

We present a bounce universe in modified $f(Q,C)$ gravity considering linear as well as exponential form of gravity. Bounce cosmological models are introduced to remove the singularity problem of the early universe. A new quadratic boundary…

广义相对论与量子宇宙学 · 物理学 2025-08-07 Bhaswati Mandal , B. C. Paul

The present work is devoted to explore some interesting cosmological features of a newly proposed theory of gravity namely $\mathcal{F}(R,L_m,T)$ theory, where $R$ and $T$ represent the Ricci scalar and trace of energy momentum-tensor,…

广义相对论与量子宇宙学 · 物理学 2024-04-09 M. Zubair , Saira Waheed , Quratulien Muneer , M. Ahmad

In this paper, we have presented a bouncing cosmological model of the Universe in an extended theory of gravity. The dynamical behaviour of the model obtained from the flat FLRW space-time along with the violation of null energy condition…

广义相对论与量子宇宙学 · 物理学 2022-04-22 A. S. Agrawal , Francisco Tello-Ortiz , B. Mishra , S. K. Tripathy

In this paper, we have presented the cosmological model of the Universe that represents late time cosmic acceleration in torsion based gravitational theory, the $f(T)$ gravity. A well motivated parametrization for the Hubble parameter has…

广义相对论与量子宇宙学 · 物理学 2025-11-04 Suraj Kumar Behera , Pratik P. Ray , B. Mishra

We investigate bouncing solutions in the framework of the non-singular gravity model of Brandenberger, Mukhanov and Sornborger. We show that a spatially flat universe filled with ordinary matter undergoing a phase of contraction reaches a…

高能物理 - 理论 · 物理学 2010-04-06 L. Raul Abramo , Patrick Peter , Ivan Yasuda

Matter and quasi-matter bounce scenarios are studied for an F(R) gravity model with holonomy corrections and a Lagrange multiplier, with a scale factor $a(t) = \left(a_0t^2 + 1 \right)^n$, where the Hubble parameter squared has a linear and…

广义相对论与量子宇宙学 · 物理学 2020-01-29 Emilio Elizalde , S. D. Odintsov , Tanmoy Paul

We investigate the divergence-free parametric form of the deceleration parameter within the simplest non-minimal matter-geometry coupling in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor.…

广义相对论与量子宇宙学 · 物理学 2025-03-11 A. Zhadyranova , M. Koussour , Zh. Kanibekova , V. Zhumabekova , U. Ismail , S. Muminov , J. Rayimbaev

In this paper, we explore the model of $f(Q,T)$ gravity, an extension of symmetric teleparallel gravity where the nonmetricity scalar $Q$ is non-minimally coupled to the trace of the energy-momentum tensor $T$. To ensure general covariance…

广义相对论与量子宇宙学 · 物理学 2025-09-09 Rahul Bhagat , Santosh V. Lohakare , B. Mishra

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

宇宙学与河外天体物理 · 物理学 2026-02-24 Mustapha Lamaaoune

The main objective of this manuscript is to investigate the bouncing cosmology in the background of $f(\mathcal{Q})$ gravity, where $\mathcal{Q}$ defines the non-metricity. For this purpose, we use the reconstruction approach and consider a…

广义相对论与量子宇宙学 · 物理学 2024-04-02 M. Sharif , M. Zeeshan Gul , Nusrat Fatima

We investigate the realization of a nonsingular cosmological bounce in metric $f(R)$ gravity using a controlled exponential deformation of the Starobinsky $R^{2}$ model. Adopting a smooth Gaussian-type bouncing scale factor, we first…

广义相对论与量子宇宙学 · 物理学 2026-03-31 G. G. L. Nashed , A. Eid

This cosmological model is a study of modified $f(Q,T)$ theory of gravity which was recently proposed by Xu {\it et al.} (Eur. Phys. J. C {\bf 79}, 708 (2019)). In this theory of gravity, the action contains an arbitrary function $f(Q,T)$…

综合物理 · 物理学 2021-09-03 Anirudh Pradhan , Archana Dixit

$f(Q,T)$ theory of gravity is very recently proposed to incorporate within the action Lagrangian, the trace $T$ of the energy-momentum tensor along with the non-metricity scalar $Q$. The cosmological application of this theory in a…

广义相对论与量子宇宙学 · 物理学 2023-05-24 Tee-How Loo , M. Koussour , Avik De

In this paper, a cosmological model of the Universe is presented in $f(Q,T)$ gravity and the parameters are constrained by cosmological data sets. Initially, a generalised form of $f(Q,T)$ model is used as $f(Q,T)=-\lambda_{1}…

广义相对论与量子宇宙学 · 物理学 2024-03-21 A. S. Agrawal , B. Mishra , S. K. Tripathy

The main objective of this study is to investigate the phenomenon of the bouncing scenario of the universe. The most widely recognized cosmological framework is the standard cosmological model, sometimes referred to as the Big Bang model.…

广义相对论与量子宇宙学 · 物理学 2024-02-13 A. S. Agrawal

We investigate which Jordan frame $F(R)$ gravity can describe a Type IV singular bouncing cosmological evolution, with special emphasis given near the point at which the Type IV singularity occurs. The cosmological bounce is chosen in such…

广义相对论与量子宇宙学 · 物理学 2015-08-06 S. D. Odintsov , V. K. Oikonomou

The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of $f(\mathcal{Q}, \mathcal{C})$ gravity, where $\mathcal{Q}$ denotes non-metricity and $\mathcal{C}$ indicates the boundary term. To…

广义相对论与量子宇宙学 · 物理学 2025-08-12 M. Sharif , M. Zeeshan Gul , Ahmad Nawaz