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Related papers: On the initial singularity in Kantowski-Sachs spac…

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In the present work, we analyzed the Kantowski-Sachs cosmological model along with teleparallel gravity, where a bulk viscous fluid containing one-dimensional cosmic strings serves as the source for the energy$-$momentum tensor. To obtain…

General Relativity and Quantum Cosmology · Physics 2024-11-11 S. R. Bhoyar , Yash B. Ingole

Solutions to flat space Friedmann-Robertson-Walker cosmologies in Brans-Dicke theory with a cosmological constant are investigated. The matter is modelled as a $\gamma$-law perfect fluid. The field equations are reduced from fourth order to…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Shawn J. Kolitch

We study cosmological braneworld models with a single timelike extra dimension. Such models admit the intriguing possibility that a contracting braneworld experiences a natural bounce without ever reaching a singular state. This feature…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yuri Shtanov , Varun Sahni

We investigate the emergent universe scenario in the presence of interacting fluids. The non-linear equation of state (EoS) considered in the general theory of relativity for obtaining emergent universe is effectively a cosmological model…

General Relativity and Quantum Cosmology · Physics 2015-05-20 B. C. Paul , A. S. Majumdar

One resolution of the ancient cosmic singularity, i.e., the Big Bang Singularity (BBS), is to assume an inflationary stage preceded by a long enough static state in which the universe and its physical properties would oscillate around…

General Relativity and Quantum Cosmology · Physics 2025-05-01 Hamid Shabani , Avik De , Tee-How Loo

Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we…

High Energy Physics - Theory · Physics 2016-11-29 Eduardo Guendelman , Ramon Herrera , Pedro Labrana , Emil Nissimov , Svetlana Pacheva

The Friedmann paradigm for a dynamical universe emanating from a spacetime singularity is critically reviwed. Quantum effects, playing the essential role at the very early stages, suggests that the universe may follow different course to…

General Relativity and Quantum Cosmology · Physics 2009-07-27 M. B. Altaie

The stability of an Einstein static universe in the DGP braneworld scenario is studied in this paper. Two separate branches denoted by $\epsilon=\pm1$ of the DGP model are analyzed. Assuming the existence of a perfect fluid with a constant…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Kaituo Zhang , Puxun Wu , Hongwei Yu

Singularity theorems demonstrate the inevitable breakdown of the concept of continuous, classical spacetime under highly general conditions. Quantum gravity is expected to intervene to avoid singularities and models so far hint towards…

General Relativity and Quantum Cosmology · Physics 2024-08-30 Raúl Carballo-Rubio , Stefano Liberati , Vania Vellucci

In the background of Friedmann-Robertson-Walker Universe, there exists Hawking radiation which comes from the cosmic apparent horizon due to quantum effect. Although the Hawking radiation on the late time evolution of the universe could be…

General Relativity and Quantum Cosmology · Physics 2012-08-02 Changjun Gao

In this work we study an alternative scheme for an Emergent Universe scenario in the context of a Jordan-Brans-Dicke theory, where the universe is initially in a truly static state supported by a scalar field located in a false vacuum. The…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Pedro Labrana , Hobby Cossio

We use a method of linearization to study the emergence of the future cosmological singularity characterized by finite value of the cosmological radius. We uncover such singularities that keep Hubble parameter finite while making all higher…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-01 A. V. Yurov

In this work, I have considered that the universe is filled with normal matter and phantom field (or tachyonic field). If the universe is filled with scalar field, Ellis et al have shown that emergent scenario is possible only for $k=+1$…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ujjal Debnath

The solution for an inflationary universe without singularities is derived from the Einstein-Lemaitre equations. The present state of the universe evolved from a steady state solution for a tiny, but classical micro-universe with large…

Astrophysics · Physics 2007-05-23 E. Rebhan

We consider Brans-Dicke cosmology with cosmological constant with negative w parameter and an arbitrary (in general non-vanishing) scale factor at the Big Bang. The field equations describe the flat universe, current observational values…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Darya Tretyakova , Alexander Shatskiy , Igor Novikov , Stanislav Alexeyev

We present a comprehensive study of cosmological singularities within the framework of Covariant Extrinsic Gravity (CEG), addressing both the initial Big Bang singularity and potential finite-time future singularities. Through detailed…

General Relativity and Quantum Cosmology · Physics 2025-04-08 R. Jalalzadeh , S. Jalalzadeh , Y. Heydarzade

Here we formulate scenario of emergent universe from particle creation mechanism in spatially flat braneworld models. We consider an isotropic and homogeneous universe in Braneworld cosmology and universe is considered as a non-equilibrium…

General Relativity and Quantum Cosmology · Physics 2016-01-20 Jibitesh Dutta , Sourav Haldar , Subenoy Chakraborty

In this work, Emergent Universe scenario has been developed in general homogeneous anisotropic model and for the inhomogeneus LTB model. In the first case, it is assumed that the matter in the universe has two components - one is perfect…

General Relativity and Quantum Cosmology · Physics 2011-11-10 Sudeshna Mukerji , Nairwita Mazumder , Ritabrata Biswas , Subenoy Chakraborty

An emergence of cosmic space has been suggested by Padmanabhan in [arXiv:1206.4916]. This new interesting approach argues that the expansion of the universe is due to the difference between the number of degrees of freedom on a holographic…

High Energy Physics - Theory · Physics 2014-04-17 Ahmed Farag Ali

Astronomical observations suggest that the Universe may be anisotropic on the largest scales. In order to model this situation, we develop a new approach to cosmology that allows for large-scale anisotropy to emerge from the growth of…

General Relativity and Quantum Cosmology · Physics 2023-06-26 Theodore Anton , Timothy Clifton