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Related papers: A Preon Model Based Universe

200 papers

We address in this work the general features of a possible compact stars composed by elementary fermions beyond the quark level. The {\it locus} of these hypothetic objects in the mass-radius plane is constructed for the maximum mass…

Astrophysics · Physics 2008-11-26 J. E. Horvath

In this work it is investigated the evolution of a Universe where a scalar field, non-minimally coupled to space-time curvature, plays the role of quintessence and drives the Universe to a present accelerated expansion. A non-relativistic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. B. Binder , G. M. Kremer

The physical instability of the Universe model with de Sitter beginning is proved in this article. 1. It is shown that even a small addition of ultrarelativistic matter turns the de Sitter Universe into the Universe with finite past. 2.…

General Relativity and Quantum Cosmology · Physics 2015-08-24 Yurii Ignat'ev

I critically examine various ad hoc models describing a fundamental minimal length at the level of the propagator. They violate causality and/or unitarity.

General Relativity and Quantum Cosmology · Physics 2015-03-17 David Campo

After recalling some puzzles in cosmology and briefly reviewing the Friedmann-Lema\^itre cosmos a simple unified model of the ``Dark Sector'' is described. This model involves a scalar field and a pseudo-scalar axion field that give rise to…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-23 Jürg Fröhlich

A preon-based composite model of the fundamental fermions is discussed, in which the fermions are bound states of smaller entities -- primitive charges (preons). The preon is regarded as a dislocation in a dual 3-dimensional manifold -- a…

General Physics · Physics 2007-05-23 V. N. Yershov

We reconsider the toy model studied in [1] of a spatially closed Friedmann-Lemaitre universe, driven by a massive scalar field, which deflates quasi-exponentially, bounces and then enters a period of standard inflation. We find that the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Nathalie Deruelle , Andreas Streich

Interpretation of cosmological data to determine the number and values of parameters describing the universe must not rely solely on statistics but involve physical insight. When statistical techniques such as "model selection" or…

Astrophysics · Physics 2011-08-31 Eric V. Linder , Ramon Miquel

Physics is introduced as a semantics of a formal set theory.

General Physics · Physics 2007-05-23 Hitoshi Kitada

The Standard Model of quarks and leptons is, at first sight, nothing but a set of {\it ad hoc} rules, with no connections, and no clues to their true background. At a closer look, however, there are many inherent prophecies that point in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sverker Fredriksson

The pre-big bang scenario describes the evolution of the Universe from an initial state approaching the flat, cold, empty, string perturbative vacuum. The choice of such an initial state is suggested by the present state of our Universe if…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. Gasperini

A cosmological model for the early time Universe is proposed. In this model, the Universe is a wandering brane moving in a warped throat of a Calabi-Yau space. A non-zero angular momentum induces a turning point in the brane trajectory, and…

High Energy Physics - Theory · Physics 2009-08-13 Cristiano Germani , N. E. Grandi , Alex Kehagias

Explaining the well established observation that the expansion rate of the universe is apparently accelerating is one of the defining scientific problems of our age. Within the standard model of cosmology, the repulsive 'dark energy'…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-20 Marco Regis , Chris Clarkson

In this paper, a cosmological model of the Universe is presented in $f(Q,T)$ gravity and the parameters are constrained by cosmological data sets. Initially, a generalised form of $f(Q,T)$ model is used as $f(Q,T)=-\lambda_{1}…

General Relativity and Quantum Cosmology · Physics 2024-03-21 A. S. Agrawal , B. Mishra , S. K. Tripathy

I describe the features and general properties of bouncing models and the evolution of cosmological perturbations on such backgrounds. I will outline possible observational consequences of the existence of a bounce in the primordial…

High Energy Physics - Theory · Physics 2009-11-10 Nelson Pinto-Neto

In a recent article R. T. Cahill claims that the cosmological model based on his "new physics of a dynamical 3-space" resolves the CMB-BBN Lithium-7 and Helium-4 abundance anomalies. In this note it is shown that this conclusion is wrong,…

General Physics · Physics 2010-02-26 Gary Steigman

It has been recently pointed out by Arkani-Hamed and Dimopoulos that if the universe is a landscape of vacua, and if therefore fine-tuning is not a valid guidance principle for searching for physics beyond the standard model, supersymmetric…

High Energy Physics - Phenomenology · Physics 2011-09-13 Xavier Calmet

We consider solutions of the cosmological equations pertaining to a dissipative, dilaton-driven off-equilibrium Liouville Cosmological model, which may describe the effective field theoretic limit of a non-critical string model of the…

High Energy Physics - Theory · Physics 2009-11-11 G. A. Diamandis , B. C. Georgalas , A. B. Lahanas , N. E. Mavromatos , D. V. Nanopoulos

This short paper proposes an alternative theory to Anthropic Principle. According to our interpretation, the Universe is not "fine-tuned" for life, but "roughly-tuned" for computation and its biofilness is only a phenomenon. This standpoint…

General Physics · Physics 2016-07-19 Zoltan Galantai

Galaxy surveys provide a large-scale view of the universe that typically has a limited line-of-sight or redshift resolution. The lack of radial accuracy in these surveys can be modelled by picturing the universe as a set of concentric…

Astrophysics · Physics 2009-11-13 P. Fosalba , E. Gaztanaga , F. Castander , M. Manera