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Related papers: On the viability of some Emergent Universe models

200 papers

A class of Emergent Universe (EU) model is studied in the light of recent observational data. Significant constraints on model parameters are obtained from the observational data. Density parameter for a class of model is evaluated. Some of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 S. Ghose , P. Thakur , B. C. Paul

A specific class of flat Emergent Universe (EU) is considered and its viability is tested in view of the recent observations. Model parameters are constrained from Stern data for Hubble Parameter and Redshift ($H(z)$ vs. $z$) and from a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 B. C. Paul , S. Ghose , P. Thakur

We study a composition of normal and exotic matter which is required for a flat Emergent Universe scenario permitted by the equation of state (EOS)($p=A\rho-B\rho^{1/2}$) and predict the range of the permissible values for the parameters…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-27 B. C. Paul , P. Thakur , S. Ghose

A cosmological scenario where dark matter interacts with a variable vacuum energy for a spatially flat Friedmann-Robertson-Walker space-time is proposed and analysed to show that with a linear equation of state and a particular interaction…

General Relativity and Quantum Cosmology · Physics 2017-09-11 Emiliano Marachlian , Iván E. Sánchez G. , Osvaldo P. Santillán

A general framework for an emergent universe scenario has been given which makes use of an equation of state. The general features of the model have also been studied and possible primordial composition of the universe have been suggested.

General Relativity and Quantum Cosmology · Physics 2009-11-11 S. Mukherjee , B. C. Paul , N. K. Dadhich , S. D. Maharaj , A. Beesham

A model of an emergent universe is formulated using the mechanism of particle creation. Here the universe is considered as a non-equilibrium thermodynamical system with dissipation due to particle creation mechanism. The universe is chosen…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Subenoy Chakraborty

The expectation of explaining cosmological observations without requiring new energy sources is forsooth worthy of investigation. In this letter, a new kind of Cardassian models, called exponential Cardassian models, for the late-time…

Astrophysics · Physics 2009-11-13 Dao-jun Liu , Chang-bo Sun , Xin-zhou Li

We investigate a flat Emergent Universe (EU) with a nonlinear equation of state which is equivalent to three different compositions of fluids. In the EU, initially, the evolution of the universe began with no interaction, but as time…

General Relativity and Quantum Cosmology · Physics 2023-09-19 Anirban Chanda , Bikash Chandra Roy , Kazuharu Bamba , Bikash Chandra Paul

The possibility of an emergent universe solution to Einstein's field equations allowing for an irreversible creation of matter at the expense of the gravitational field is shown. With the universe being chosen as spatially flat FRW…

General Relativity and Quantum Cosmology · Physics 2016-09-27 Sunandan Gangopadhyay , Anirban Saha , S. Mukherjee

We study the cosmological stability of a class of theories with a dynamical preferred frame. For a range of actions, we find cosmological solutions which are compatible with observations of the recent history of the Universe: a matter…

Astrophysics · Physics 2009-06-23 T. G Zlosnik , P. G. Ferreira , G. D. Starkman

A class of models intended to be as minimal and structureless as possible is introduced. Even in cases with simple rules, rich and complex behavior is found to emerge, and striking correspondences to some important core known features of…

Discrete Mathematics · Computer Science 2020-10-07 Stephen Wolfram

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

The phenomenon of emergent physics in condensed-matter many-body systems has become the paradigm of modern physics, and can probably also be applied to high-energy physics and cosmology. This encouraging fact comes from the universal…

Strongly Correlated Electrons · Physics 2009-11-11 G. E. Volovik

In the present work, the flat FLRW Universe has been modelled with cosmic matter in the form of diffusive barotropic fluid. The diffusive fluid undergoes dissipation due to diffusion mechanism in the form of cosmological scalar field. From…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Subhayan Maity , Subenoy Chakraborty

In this paper, we attempt to explore the possibility of a obtaining a viable emergent universe scenario supported by a type of fluid known as the extended Chaplygin gas, which extends a modification to the equation of state of the well…

General Relativity and Quantum Cosmology · Physics 2025-08-13 Rikpratik Sengupta , Anirban Chanda , B C Paul , M Kalam

We explore the possibility of emergent cosmology using the effective potential formalism. We discover new models of emergent cosmology which satisfy the constraints posed by the cosmic microwave background (CMB). We demonstrate that, within…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Satadru Bag , Varun Sahni , Yuri Shtanov , Sanil Unnikrishnan

The first cosmological results from the ESSENCE supernova survey (Wood-Vasey et al. 2007) are extended to a wider range of cosmological models including dynamical dark energy and non-standard cosmological models. We fold in a greater number…

A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…

Astrophysics · Physics 2009-06-23 S. Capozziello

Keeping in mind the current picture of an accelerating and flat Universe, some specific dynamical models of the cosmological term $\Lambda$ have been selected for investigating the nature of dark energy. Connecting the free parameters of…

Astrophysics · Physics 2008-11-26 Saibal Ray , Utpal Mukhopadhyay , Xin-He Meng

In this work we explore a model of the universe in which dark energy is modelled explicitely with both a dynamical quintessence field (with a double exponential self-interaction potential) and a cosmological constant. For a given region of…

Astrophysics · Physics 2007-05-23 Rolando Cardenas , Tame Gonzalez , Osmel Martin , Israel Quiros
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