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We present a nonsingular bouncing cosmology using single scalar field matter with non-trivial potential and non-standard kinetic term. The potential sources a dynamical attractor solution with Ekpyrotic contraction which washes out small…

High Energy Physics - Theory · Physics 2012-08-21 Yi-Fu Cai , Damien A. Easson , Robert Brandenberger

Scenario of a bouncing universe is one of the most active area of research to arrive at singularity free cosmological models. Different proposals have been suggested to avoid the so called 'big bang' singularity through the quantum aspect…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Indrani Banerjee , Tanmoy Paul , Soumitra SenGupta

We explore dynamics of cosmological models with bounce solutions evolving on a spatially flat Friedmann-Lemaitre-Robertson-Walker background. We consider cosmological models that contain the Hilbert-Einstein curvature term, the induced…

General Relativity and Quantum Cosmology · Physics 2016-12-08 Ekaterina O. Pozdeeva , Maria A. Skugoreva , Alexey V. Toporensky , Sergey Yu. Vernov

By studying some bouncing universe models dominated by a specific class of hydrodynamical fluids, we show that the primordial cosmological perturbations may propagate smoothly through a general relativistic bounce. We also find that the…

High Energy Physics - Theory · Physics 2009-11-10 Patrick Peter , Nelson Pinto-Neto , Diego A. Gonzalez

The recent transition from decelerated to accelerated expansion can be seen as a reflection (or "bounce") in the connection variable, defined by the inverse comoving Hubble length ($b=\dot a$, on-shell). We study the quantum cosmology of…

General Relativity and Quantum Cosmology · Physics 2022-10-06 Bruno Alexandre , Joao Magueijo

In this letter, we propose a new generalized mass-to-horizon relation to be used in the context of entropic cosmologies and holographic principle scenarios. We show that a general scaling of the mass with the Universe horizon as $M=\gamma…

General Relativity and Quantum Cosmology · Physics 2024-05-02 Hussain Gohar , Vincenzo Salzano

We review the general features of nonsingular universes ({\em i.e.} those that go from an era of accelerated collapse to an expanding era without displaying a singularity) as well as cyclic universes. We discuss the mechanisms behind the…

Astrophysics · Physics 2008-12-18 M. Novello , S. E. Perez Bergliaffa

As our understanding of the past in a bouncing universe is limited, it becomes difficult to propose a cosmological model which can give some understanding of the causal structure of the bouncing universe. In this article we address the…

General Relativity and Quantum Cosmology · Physics 2018-09-12 Kaushik Bhattacharya , Pritha Bari , Saikat Chakraborty

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 M. Koussour , N. Myrzakulov

We explore bounce scenarios in the framework of homogeneous and isotropic cosmological models with arbitrary spatial curvature in the theory of gravity with non-minimal derivative coupling. As expected, we find that there are no turning…

General Relativity and Quantum Cosmology · Physics 2025-02-11 S. V. Sushkov , R. G. Galeev

The present manuscript presents modeling of matter bounce in the framework of $f(R,T)$ gravity where $f(R,T) = R + 2 \lambda T$. We start by defining a parametrization of scale factor which is non-vanishing. The geometrical parameters such…

General Relativity and Quantum Cosmology · Physics 2020-02-04 Parbati Sahoo , S. Bhattacharjee , S. K. Tripathy , P. K. Sahoo

In this manuscript, we investigate the patterns satisfied by the cosmological anisotropy under the hypothesis of the observers being co-moving with a perfect fluid whose induced space sections are homogeneous with vanishing scalar…

General Relativity and Quantum Cosmology · Physics 2021-03-31 Leandro G. Gomes

The big bounce singularity of a simple 5D cosmological model is studied. Contrary to the standard big bang space-time singularity, this big bounce singularity is found to be an event horizon at which the scale factor and the mass density of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Lixin Xu , Hongya Liu , Beili Wang

Background boucing cosmologies in the framework of General Relativity, driven by a single scalar field filling the Universe, and with a quasi-matter domination period, i.e., depicting the so-called Matter Bounce Scenario, are reconstructed…

General Relativity and Quantum Cosmology · Physics 2017-03-22 Jaume de Haro

Homogeneous and isotropic, nonsingular, bouncing world models are designed to evade the initial singularity at the beginning of the cosmic expansion. Here, we study the thermodynamics of the subset of these models governed by general…

General Relativity and Quantum Cosmology · Physics 2016-03-09 Pedro C. Ferreira , Diego Pavon

We examine the second law of thermodynamics in the context of horizon cosmology, in particular, whether the change of total entropy (i.e. the sum of the entropy for the apparent horizon and the entropy for the matter fields) proves to be…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Sergei D. Odintsov , Tanmoy Paul , Soumitra SenGupta

This essay is a brief review of the recent studies of non-singular cosmological scenarios with bounce and Genesis and their stability in a subclass of scalar-tensor theories with higher derivatives -- beyond Horndeski theories. We discuss…

High Energy Physics - Theory · Physics 2019-09-13 S. Mironov , V. Rubakov , V. Volkova

This article gives a concise overview of the development and current status of studies on healthy models of the early Universe without an initial singularity, namely the cosmological bounce and Genesis scenarios, constructed within a broad…

General Relativity and Quantum Cosmology · Physics 2025-01-20 S. Mironov , V. Volkova

We investigate the generation of the baryon asymmetry within the cosmological framework based on a generalized mass-to-horizon entropy. This entropy, recently proposed as a power-law extension of the Bekenstein-Hawking area law, arises from…

General Relativity and Quantum Cosmology · Physics 2025-11-04 Giuseppe Gaetano Luciano , Emmanuel N. Saridakis

The absence of isotropic singularity in loop quantum cosmology can be understood in an effective classical description as the universe exhibiting a Big Bounce. We show that with scalar matter field, the big bounce is generic in the sense…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ghanashyam Date , Golam Mortuza Hossain