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Related papers: Singularities and Cyclic Universes

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For spacetimes containing quiescent singularity hypersurfaces we propose a general notion of junction conditions based on a prescribed singularity scattering map, as we call it, and we introduce the notion of a cyclic spacetime (also called…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Bruno Le Floch , Philippe G. LeFloch , Gabriele Veneziano

The formulation of the alternative theory of neutrino oscillations is presented. Also the application of that theory to a system of neutrinos produced by a source is formulated and some basic formulae are derived.

High Energy Physics - Phenomenology · Physics 2007-05-23 Viliam Pazma , Julius Vanko

We review recent work and present new examples about the character of singularities in globally and regularly hyperbolic, isotropic universes. These include recent singular relativistic models, tachyonic and phantom universes as well as…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Spiros Cotsakis , Ifigeneia Klaoudatou

The off-site continuums are proposed for the cosmological models of the galaxies and the Universe. It is shown that many visual properties of galaxies and the Universe may be described on frames of the off-site continuums methodology. In…

General Physics · Physics 2008-12-12 A. V. Novikov-Borodin

The evolution of a class of inhomogeneous spherically symmetric universe models possessing a varying cosmological term and a material fluid, with an adiabatic index either constant or not, is studied.

General Relativity and Quantum Cosmology · Physics 2015-06-25 Luis P. Chimento , Diego Pavon

Complete cosmic evolution is a popular model in cosmology. But the possibility of other different cosmic evolution model can not be negated. The nonsingular bouncing scenario models are now found in literature. This work is a representation…

General Relativity and Quantum Cosmology · Physics 2022-05-23 Subhayan Maity

I give a compact, pedagogical review of our present understanding of the universe as based on general relativity. This includes the uniform models, with special reference to the cosmological 'constant'; and the equations for…

General Relativity and Quantum Cosmology · Physics 2012-08-17 Paul S. Wesson

A relativistic modified gravity (MOG) theory leads to a self-consistent, stable gravity theory that can describe the solar system, galaxy and clusters of galaxies data and cosmology.

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. W. Moffat

Basis and limitations of singularity theorems for Gravity are examined. As singularity is a critical situation in course of time, study of time paths, in full generality of Equivalence principle, provides two mechanisms to prevent…

General Relativity and Quantum Cosmology · Physics 2007-05-23 K. H. Mariwalla

Five-vectors theory of gravity is proposed, which admits an arbitrary choice of the energy density reference level. This theory is formulated as the constraint theory, where the Lagrange multipliers turn out to be restricted to some class…

General Relativity and Quantum Cosmology · Physics 2019-04-02 S. L. Cherkas , V. L. Kalashnikov

In this report we discuss three aspects: 1) Semiclassical gravity theory (SCG): 4 levels of theories describing the interaction of quantum matter with classical gravity; 2) Alternative Quantum Theories: Discerning those which are derivable…

General Relativity and Quantum Cosmology · Physics 2015-06-18 B. L. Hu

The idea of a multiverse -- an ensemble of universes -- has received increasing attention in cosmology, both as the outcome of the originating process that generated our own universe, and as an explanation for why our universe appears to be…

Astrophysics · Physics 2008-11-26 G. F. R. Ellis , U. Kirchner , W. R. Stoeger

We investigate homogeneous and isotropic oscillating cosmologies with multiple fluid components. Transfer of energy between these fluids is included in order to model the effects of non-equilibrium behavior on closed universes. We find…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Clifton , John D. Barrow

Cosmological models that invoke a multiverse - a collection of unobservable regions of space where conditions are very different from the region around us - are controversial, on the grounds that unobservable phenomena shouldn't play a…

History and Philosophy of Physics · Physics 2018-01-17 Sean M. Carroll

The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Albert V. Minkevich

In this letter, we consider cosmological solutions of bimetric theory without assuming that only one metric is coupled to gravity. We conclude that any cosmology can be described by fixing the matter content of the space that we are not…

General Relativity and Quantum Cosmology · Physics 2013-01-21 Salvatore Capozziello , Prado Martin-Moruno

Combining intervals of ekpyrotic (ultra-slow) contraction with a (non-singular) classical bounce naturally leads to a novel cyclic theory of the universe in which the Hubble parameter, energy density and temperature oscillate periodically,…

General Relativity and Quantum Cosmology · Physics 2019-07-12 Anna Ijjas , Paul J. Steinhardt

Partial descriptions of the Universe are presented in the form of linear equations considered in the free (full, super) Fock space. The universal properties of these equations are discussed. The closure problem caused by computational and…

General Physics · Physics 2010-10-19 Jerzy Hanckowiak

The actual existence of collections of universes -- multiverses -- is strongly suggested by leading approaches to quantum cosmology, and has been proposed earlier as an attractive way to explain the apparent fine-tuned character of our…

Astrophysics · Physics 2007-05-23 William R. Stoeger

A new approach to special relativity is presented which introduces coordinate systems with imaginary time axes, observation systems, and coordinate bases.

General Physics · Physics 2008-05-17 Y. -H. Choi