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Related papers: Emergent scenario in mimetic gravity

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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 shall in the framework of Bohmian quantum gravity show that it is possible to find a {\it pure} quantum state which leads to the static Einstein universe whose classical counterpart is flat space--time. We obtain the solution not only in…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. Shojai , F. Shojai , N. Dadhich

We consider a non singular origin for the Universe starting from an Einstein static Universe, the so called "emergent universe" scenario, in the framework of a theory which uses two volume elements $\sqrt{-{g}}d^{4}x$ and $\Phi d^{4}x$,…

General Relativity and Quantum Cosmology · Physics 2015-05-27 E. I. Guendelman

We consider fluctuations in a perfect irrotational fluid coupled to gravity in an Einstein static universe background. We show that the homogeneous linear perturbations of the scalar and metric fluctuations in the Einstein static universe…

General Relativity and Quantum Cosmology · Physics 2009-11-10 B. Losic , W. G. Unruh

We address issues on the origin of gravity and the dark energy (or the cosmological constant) from the perspectives of emergent gravity. We discuss how the emergent gravity reveals a noble, radically different picture about the origin of…

High Energy Physics - Theory · Physics 2008-11-26 Hyun Seok Yang

Since the advent of inflation, several theorems have been proven suggesting that although inflation can (and generically does) continue eternally into the future, it cannot be extended eternally into the past to create a ``steady-state''…

Astrophysics · Physics 2009-11-07 Anthony Aguirre , Steven Gratton

The stability properties of the Einstein Static solution of General Relativity are altered when corrective terms arising from modification of the underlying gravitational theory appear in the cosmological equations. In this paper the…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Rosangela Canonico , Luca Parisi

We analyze the stability of the Einstein static universe by considering homogeneous perturbations in the context of f(G) modified Gauss-Bonnet theories of gravity. By considering a generic form of f(G), the stability region of the Einstein…

General Relativity and Quantum Cosmology · Physics 2009-03-30 Christian G. Boehmer , Francisco S. N. Lobo

A first order inflation model where a gauge coupling constant runs as the universe inflates is investigated. This model can solve the graceful-exit problem within Einstein gravity by varying the bubble formation rate. The sufficient…

High Energy Physics - Phenomenology · Physics 2008-02-03 Jae-weon Lee , In-guy Koh

To seek for a singularity free model universe from a perfect fluid scalar-metric cosmology, we work in the "\emph{Emergent Cosmology}" (EC) paradigm which is a non-singular alternative for cosmological inflation. By using two methods…

General Relativity and Quantum Cosmology · Physics 2018-06-26 Mohsen Khodadi , Kourosh Nozari

We consider the Einstein static and the de Sitter universe solutions and examine their instabilities in a subclass of quadratic modified theories for gravity. This modification proposed by Nash is an attempt to generalize general…

General Physics · Physics 2021-04-01 Mudhahir Al Ajmi

The Fermi-point scenario of emergent gravity has the following consequences: gravity emerges together with fermionic and bosonic matter; emergent fermionic matter consists of massless Weyl fermions; emergent bosonic matter consists of gauge…

General Relativity and Quantum Cosmology · Physics 2008-11-26 G. E. Volovik

We address issues on the origin of gravity and the cosmological constant problem based on a recent understanding about the correspondence between noncommutative field theory and gravity. We suggest that the cosmological constant problem can…

High Energy Physics - Theory · Physics 2008-03-28 Hyun Seok Yang

A simple model for a scalar field and gravity admits homogeneous isotropic cosmological solutions which cross the Big Bang singularity. In the scaling frame with field dependent effective Planck mass these solutions are regular. They become…

General Relativity and Quantum Cosmology · Physics 2021-07-27 C. Wetterich

We show using covariant techniques that the Einstein static universe containing a perfect fluid is always neutrally stable against small inhomogeneous vector and tensor perturbations and neutrally stable against adiabatic scalar density…

General Relativity and Quantum Cosmology · Physics 2011-07-19 John D Barrow , George Ellis , Roy Maartens , Christos Tsagas

In this essay we marshal evidence suggesting that Einstein gravity may be an emergent phenomenon, one that is not ``fundamental'' but rather is an almost automatic low-energy long-distance consequence of a wide class of theories.…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Carlos Barcelo , Matt Visser , Stefano Liberati

Using a long wavelength iteration scheme to solve Einstein's equations near the Big-Bang singularity of a universe driven by a massive scalar field, we find how big initial quasi-isotropic inhomogeneities can be before they can prevent…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Nathalie Deruelle , Dalia S. Goldwirth

Matrix theory is a proposed non-perturbative definition of superstring theory in which space is emergent. We begin a study of cosmology in the context of matrix theory. Specifically, we show that matrix theory can lead to an emergent…

High Energy Physics - Theory · Physics 2022-03-30 Suddhasattwa Brahma , Robert Brandenberger , Samuel Laliberte

In contrast to the phenomenon of nullification of the cosmological constant in the equilibrium vacuum, which is the general property of any quantum vacuum, there are many options in modifying the Einstein equation to allow the cosmological…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. E. Volovik

Inflation has been the leading early universe scenario for two decades, and has become an accepted element of the successful `cosmic concordance' model. However, there are many puzzling features of the resulting theory. It requires both…

High Energy Physics - Theory · Physics 2009-11-10 Neil Turok , Paul J. Seinhardt
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