中文
相关论文

相关论文: Nonsingular bouncing cosmologies in light of BICEP…

200 篇论文

This study explores the bouncing solutions within the framework of modified $f(Q, L_m)$ gravity. We examine four prominent bouncing models, the symmetric bounce, super bounce, oscillatory bounce, and matter bounce, each of which has been…

广义相对论与量子宇宙学 · 物理学 2026-04-28 S. A. Kadam , V. A. Kshirsagar , Santosh Kumar Yadav

In this article, we explore the homogeneous and isotropic flat Friedmann-Robertson-Walker (FRW) model in Chameleon cosmology. By considering a non-minimal coupling between the scalar field and matter, we present a non-singular bouncing…

广义相对论与量子宇宙学 · 物理学 2022-12-06 Ashutosh Singh , Anirudh Pradhan

A nonsingular bouncing cosmology in which the scales of interest today exit the Hubble radius in a matter-dominated contracting phase yields an alternative to inflation for producing a scale-invariant spectrum of adiabatic cosmological…

宇宙学与河外天体物理 · 物理学 2009-05-21 Yi-Fu Cai , Wei Xue , Robert Brandenberger , Xinmin Zhang

Analyzing quantum cosmological scenarios containing one scalar field with exponential potential, we have obtained a universe model which realizes a classical dust contraction from very large scales, the initial repeller of the model, and…

广义相对论与量子宇宙学 · 物理学 2017-09-13 Samuel Colin , Nelson Pinto-Neto

We investigate non-singular bounce realizations in the framework of ghost-free generalized Galileon cosmology, which furthermore can be free of the anisotropy problem. Considering an Ekpyrotic-like potential we can obtain a total…

宇宙学与河外天体物理 · 物理学 2013-09-18 Taotao Qiu , Xian Gao , Emmanuel N. Saridakis

We explore the dynamics of FLRW cosmologies which consist of dark matter, radiation and dark energy with a quadratic equation of state. Standard cosmological singularities arise due to energy conditions which are violated by dark energy,…

广义相对论与量子宇宙学 · 物理学 2023-05-19 Molly Burkmar , Marco Bruni

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

In this paper, we model the bounce phase, stability, and the reconstruction of the universe by non-minimal kinetic coupling. In the process, we obtained importance information about the energy density and the matter pressure of the universe…

广义相对论与量子宇宙学 · 物理学 2026-02-10 Alireza Amani , A. S. Kubeka , E. Mahichi

We study the cosmology of a Lee-Wick type scalar field theory. First, we consider homogeneous and isotropic background solutions and find that they are nonsingular, leading to cosmological bounces. Next, we analyze the spectrum of…

高能物理 - 理论 · 物理学 2009-11-18 Yi-Fu Cai , Taotao Qiu , Robert Brandenberger , Xinmin Zhang

Non-perturbative quantum geometric effects in Loop Quantum Cosmology predict a $\rho^2$ modification to the Friedmann equation at high energies. The quadratic term is negative definite and can lead to generic bounces when the matter energy…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Parampreet Singh , Kevin Vandersloot , G. V. Vereshchagin

The occurrence of a bounce in FRW cosmology requires modifications of general relativity. An example of such a modification is the recently proposed Horava-Lifshitz theory of gravity, which includes a ``dark radiation'' term with a negative…

高能物理 - 理论 · 物理学 2011-03-31 Ewa Czuchry

This paper is devoted to examining cosmological bouncing scenarios in the framework of the recently proposed symmetric teleparallel gravity (or $f(Q)$ gravity), where the non-metricity scalar $Q$ represents the gravitational interaction. We…

宇宙学与河外天体物理 · 物理学 2024-09-17 M. Koussour , N. Myrzakulov

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

I present a streamlined review of how the separate universe approach to cosmological perturbation theory can be used to study the dynamics of long-wavelength scalar perturbations in loop quantum cosmology, and then use it to calculate how…

广义相对论与量子宇宙学 · 物理学 2016-08-03 Edward Wilson-Ewing

Bouncing non-singular isotropic cosmological solutions are investigated in a simple model of scalar-tensor gravity. New families of such solutions are found and their properties are presented and analyzed using an effective potential as the…

广义相对论与量子宇宙学 · 物理学 2022-01-28 D. Polarski , A. A. Starobinsky , Y. Verbin

We explore the isotropization of a model anisotropic universe in the bouncing models using the ekpyrotic potential without assuming initial conditions corresponding to an ekpyrotic phase. In particular, we explore the way the use of…

广义相对论与量子宇宙学 · 物理学 2025-12-11 Rachel Brown , A. Meenakshi McNamara , Sahil Saini , Parampreet Singh

We study a model for a non-singular cosmic bounce in N=1 supergravity, based on supergravity versions of the ghost condensate and cubic Galileon scalar field theories. The bounce is preceded by an ekpyrotic contracting phase which prevents…

高能物理 - 理论 · 物理学 2014-08-13 Michael Koehn , Jean-Luc Lehners , Burt A. Ovrut

In this work we study non-singular{ bounce cosmology} in the context of the Lagrange multiplier generalized $F(R)$ gravity theory of gravity. We specify our study by using a specific variant form of the well known matter{ bounce cosmology},…

广义相对论与量子宇宙学 · 物理学 2020-01-08 Shin'ichi Nojiri , S. D. Odintsov , V. K. Oikonomou , Tanmoy Paul

In recent years, Loop Quantum Gravity has emerged as a solid candidate for a nonperturbative quantum theory of General Relativity. It is a background independent theory based on a description of the gravitational field in terms of…

广义相对论与量子宇宙学 · 物理学 2009-10-16 Guillermo A. Mena Marugan

We investigate cosmological scenarios with a non-minimal derivative coupling between the scalar field and the curvature, examining both the quintessence and the phantom cases in zero and constant potentials. In general, we find that the…

广义相对论与量子宇宙学 · 物理学 2010-04-21 Emmanuel N. Saridakis , Sergey V. Sushkov