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We solve Einstein's equation with Robertson-Walker metric as an initial-value problem, using as the source of gravity a Halpern-Huang real scalar field, which was derived from renormalization-group analysis, with a potential that exhibits…

General Relativity and Quantum Cosmology · Physics 2010-11-18 Kerson Huang , Hwee-Boon Low , Roh-Suan Tung

A new phenomenological theory for the expansion of our universe is presented. Because fundamental supporting theory is still in development, its discussion is not presented in this paper. The theory is based on a new algebraic expression…

General Physics · Physics 2011-01-26 Charles B. Leffert

Cosmological perturbations in the (1+3+6)-dimensional space-times including photon gas without viscous processes are studied on the basis of Abbott et al.'s formalism. Space-times consist of the outer space (the 3-dimensional expanding…

General Relativity and Quantum Cosmology · Physics 2014-12-23 Kenji Tomita

Over the past three years we have determined the basic features of our Universe. It is spatially flat; accelerating; comprised of 1/3 a new form of matter, 2/3 a new form of energy, with some ordinary matter and a dash of massive neutrinos;…

Astrophysics · Physics 2008-11-26 Michael S. Turner

We consider the quantized bi-scalar gravity, which may serve as a locally Lorentz invariant cosmological model with varying speed of light and varying gravitational constant. The equation governing the quantum regime for the case of…

General Relativity and Quantum Cosmology · Physics 2023-10-02 Adam Balcerzak , Mateusz Lisaj

The $\rm\Lambda$CDM cosmological model is remarkable: with just 6 parameters it describes the evolution of the Universe from a very early time when all structures were quantum fluctuations on subatomic scales to the present, and it is…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-07 Michael S. Turner

We conduct a case study analysis of a proposal for the emergence of time based upon the approximate derivation of three grades of temporal structure within an explicit quantum cosmological model which obeys a Wheeler-DeWitt type equation…

General Relativity and Quantum Cosmology · Physics 2023-10-18 Nick Huggett , Karim P. Y. Thébault

A supersymmetric Yang-Mills system in (11,3) dimensions is constructed with the aid of two mutually orthogonal null vectors which naturally arise in a generalized spacetime superalgebra. An obstacle encountered in an attempt to extend this…

High Energy Physics - Theory · Physics 2009-10-30 Ergin Sezgin

We consider a scenario where our universe is taken as a three-dimensional domain wall embedded in a five-dimensional Minkowski space-time, as originally proposed by Brito and collaborators [1]. We explore the existence of a richer class of…

High Energy Physics - Theory · Physics 2009-04-01 A. de Souza Dutra , A. C. Amaro de Faria , M. Hott

In this paper we study a class of inhomogeneous cosmological models which is a modified version of what is usually called the Lema\^itre-Tolman model. We assume that we have a space with 2-dimensional locally homogeneous spacelike surfaces.…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sigbjorn Hervik

In this contribution we identify two scenarios for the evolutionary branch cut universe. In the first scenario, the universe evolves continuously from the negative complex cosmological time sector, prior to a primordial singularity, to the…

General Relativity and Quantum Cosmology · Physics 2021-05-19 C. A. Z. Vasconcellos , P. O. Hess , D. Hadjimichef , B. Bodmann , M. Razeira , G. L. Volkmer

In a compact space with non-trivial cycles, for sufficiently small values of the compact dimensions, charge conjugation (C), spatial reflection (P) and time reversal (T) are spontaneously broken in QCD. The order parameter for the symmetry…

High Energy Physics - Lattice · Physics 2008-11-26 Biagio Lucini , Agostino Patella , Claudio Pica

During Big Bang Nucleosynthesis (BBN), in the first 20 minutes of the evolution of the Universe, the light nuclides, D, 3He, 4He, and 7Li were synthesized in astrophysically interesting abundances. The Cosmic Microwave Background Radiation…

Astrophysics · Physics 2008-07-21 Gary Steigman

We consider a solution of a IKKT-type matrix model which can be considered as a 1+1-dimensional space-time with Minkowski signature and a Big Bounce-like singularity. A suitable $i\varepsilon$ regularization of the Lorentzian matrix…

High Energy Physics - Theory · Physics 2023-04-12 Joanna L. Karczmarek , Harold C. Steinacker

After a brief introduction to the sixteenth and seventeenth century views of the Universe and the nineteenth century paradox of Olbers, we start the history of the cosmic expansion with Hubble's epochal discovery of the recession velocities…

Astrophysics · Physics 2008-02-15 Matts Roos

We propose a cosmological model in which the universe undergoes an endless sequence of cosmic epochs each beginning with a `bang' and ending in a `crunch.' The temperature and density are finite at each transition from crunch to bang.…

High Energy Physics - Theory · Physics 2009-11-07 Paul J. Steinhardt , Neil Turok

We present four-dimensional gauge theories in Minkowski spacetime which effectively generate in certain energy regimes five-dimensional warped geometries whereas, in general, the fifth dimension is latticized. After discussing in detail…

High Energy Physics - Theory · Physics 2009-11-07 Konstadinos Sfetsos

Some long standing issues concerning the quantum nature of the big bang are resolved in the context of homogeneous isotropic models with a scalar field. Specifically, the known results on the resolution of the big bang singularity in loop…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh

We consider a rather simple method for the description of the Big Bang - Big Crunch cosmological singularity crossing. For the flat Friedmann universe this method gives the same results as more complicated methods, using Weyl symmetry or…

General Relativity and Quantum Cosmology · Physics 2017-04-12 Alexander Yu. Kamenshchik , Ekaterina O. Pozdeeva , Sergey Yu. Vernov , Alessandro Tronconi , Giovanni Venturi

We consider a (4+d)-dimensional spacetime broken up into a (4-n)-dimensional Minkowski spacetime (where n goes from 1 to 3) and a compact (n+d)-dimensional manifold. At the present time the n compactification radii are of the order of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 A. G. Agnese , M. La Camera
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