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Related papers: Emergent scenario in mimetic gravity

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We derive here the metric for Einstein's static universe (ESU) directly from Einstein equation, i.e., by considering both $G_{ik}$ and $T_{ik}$. We find that in order that the fluid pressure and acceleration are {\em uniform} and finite…

General Physics · Physics 2008-08-19 Abhas Mitra

Many models of high energy physics possess metastable vacua. It is conceivable that the universe can get trapped in such a false vacuum, irrespective of its origin and prior history, at an earlier stage during its evolution. The ensuing…

High Energy Physics - Phenomenology · Physics 2008-12-18 Rouzbeh Allahverdi , Bhaskar Dutta , Anupam Mazumdar

For variable gravity models the strength of gravity, as measured by Newton's ``constant'' or the Planck mass, depends on the value of a scalar field, the cosmon. We discuss two simple four-parameter models with a quadratic or constant…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-15 C. Wetterich

We consider a scale invariant model which includes a $R^{2}$ term in action and show that a stable "emerging universe" scenario is possible. The model belongs to the general class of theories, where an integration measure independent of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Sergio del Campo , Eduardo Guendelman , Ramon Herrera , Pedro Labrana

Scenario bouncing can give the cosmology singularity problem a possible way out. Finding a solution for the universe's bouncing model requires proper estimation of the state equation. We present two such state equations that give us the…

General Relativity and Quantum Cosmology · Physics 2020-12-29 C. Swastik , P K Suresh , Barun Maity

The cosmological constant is one of the most pressing problems in modern physics. We address this issue from an emergent gravity standpoint, by using an analogue gravity model. Indeed, the dynamics of the emergent metric in a Bose-Einstein…

General Relativity and Quantum Cosmology · Physics 2012-02-29 Stefano Finazzi , Stefano Liberati , Lorenzo Sindoni

We propose a mechanism where the dynamical generation of the Planck mass in scale invariant gravity leads to Einstein gravity, successful inflation and an explanation of the hierarchy problem of the Standard Model. We will discuss the scale…

High Energy Physics - Phenomenology · Physics 2025-12-01 Thede de Boer , Jisuke Kubo , Manfred Lindner , Markus Reinig

Let us assume that gravity is an emergent low-energy phenomenon arising from a topologically stable defect in momentum space -- the Fermi point. What are the consequences? We discuss the natural values of fermion masses and cosmological…

General Relativity and Quantum Cosmology · Physics 2008-02-26 G. E. Volovik

Singularities in General Relativity are regions where the description of spacetime in terms of a pseudo-Riemannian geometry breaks down. The theory seems unable to predict the evolution of the physical degrees of freedom around and beyond…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Flavio Mercati

In the standard inflationary paradigm the inhomogeneities observed in the CMB arise from quantum fluctuations of an initially homogeneous and isotropic vacuum state. This picture suffers from two well-known weaknesses. First, it assumes…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Gabriel R. Bengochea , Gabriel Leon , Alejandro Perez

The stability of cosmological solutions in the recently suggested specific mechanism of dynamical compensation of vacuum energy is studied. It is found that the solutions in the original version lead to cosmological singularity which could…

Astrophysics · Physics 2007-05-23 A. D. Dolgov , M. Kawasaki

Dynamical systems methods are used to investigate a cosmological model with non-minimally coupled scalar field and asymptotically quadratic potential function. We found that for values of the non-minimal coupling constant parameter…

General Relativity and Quantum Cosmology · Physics 2021-07-15 Orest Hrycyna

In a recent paper it was suggested that inclusion of mutual gravitational interactions among the collapsing particles can avert a singularity and give finite value for various physical quantities. In this paper we extend this idea further…

Astrophysics · Physics 2008-06-26 C Sivaram , Kenath Arun , Venkata Manohara Reddy A

We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements $\sqrt{-{g}}d^{4}x$ and $\Phi d^{4}x$, where $\Phi $ is a metric independent density,…

General Relativity and Quantum Cosmology · Physics 2013-06-24 E. I. Guendelman

In Brans-Dicke theory the Universe becomes divided after inflation into many exponentially large domains with different values of the effective gravitational constant. Such a process can be described by diffusion equations for the…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Juan Garcia-Bellido , Andrei Linde

The hypothesis that gravitational self-binding energy may be the source for the vacuum energy term of cosmology is studied in a Newtonian Ansatz. For spherical spaces the attractive force of gravitation and the negative pressure of the…

General Relativity and Quantum Cosmology · Physics 2007-10-02 Erhard Scholz

Emergent scenario of cosmic evolution is a topic of great interest in recent cosmology, especially because it describes a non-singular origin of the Universe unlike the Big-Bang models. This types of cosmic evolution pattern have already…

General Relativity and Quantum Cosmology · Physics 2023-09-01 Subhayan Maity , Sujayita Bakra

KKLT give a mechanism to generate de Sitter vacua in string theory. And recently, the scenario, {\em landscape}, is suggested to explain the problem of the cosmological constant. In this scenario, the cosmological constant is a de Sitter…

High Energy Physics - Theory · Physics 2009-07-06 C. Y. Sun , D. H. Zhang

This paper introduces several ideas of emergent gravity, which come from a system similar to an ensemble of quantum spin-$\tfrac{1}{2}$ particles. To derive a physically relevant theory, the model is constructed by quantizing a scalar field…

General Relativity and Quantum Cosmology · Physics 2024-05-07 Quentin Ansel

In this work we study the stability of the Jordan-Brans-Dicke (JBD) static universe. This is motivated by the possibility that the universe might have started out in an asymptotically JBD static state, in the context of the so called…

General Relativity and Quantum Cosmology · Physics 2009-07-22 Sergio del Campo , Ramon Herrera , Pedro Labrana
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