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Related papers: Why the Universe is Just So

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I start by defining the cosmological parameters $H_0, \Omega_m$ and $\Omega_\Lambda$. Then I show how the age of the universe depends on them, followed by the evolution of the scale parameter of the universe for various values of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Palash B. Pal

In this paper we construct a physical modelization of the universe expansion. The universe then reduces to a Riemannian space $0.2cm$ $(B(O,R(t)),g_t)$, where $R(t) \sim t$ for $t \gg $0, and $g_t$ is a time - dependent Riemannian metric…

General Physics · Physics 2012-10-10 Moukaddem Nazih

The flat matter dominated Universe that dominated cosmological model building for much of the past 20 years does not correspond to the Universe in which we live. This has profound implications both for our understanding of dark matter, and…

Astrophysics · Physics 2007-05-23 Lawrence M. Krauss

The Standard Model of cosmology states a surprising composition of the Universe, in which ordinary matter accounts for less than 5%. The remaining 95% are composed of ~70% Dark Energy and ~25% Dark Matter. However, those two components have…

Astrophysics · Physics 2008-11-14 A. Benoit-Lévy , G. Chardin

It is a mystery why the density of matter and the density of vacuum energy are nearly equal today when they scale so differently during the expansion of the Universe. We suggest a paradigm that might allow for a non-anthropic solution to…

Astrophysics · Physics 2009-11-07 Kim Griest

The development of science and technology has progressively demonstrated the ability of humankind to understand and manipulate the physical world, and it has also shown some fundamental limitations to predictability of physical events. This…

History and Philosophy of Physics · Physics 2022-06-03 Ezequiel López-Rubio

A general overview of neutrino physics and astrophysics is given, starting with a historical account of the development of our understanding of neutrinos and how they helped to unravel the structure of the Standard Model. We discuss why it…

Astrophysics · Physics 2007-05-23 Esteban Roulet

We study a fundamental issue in cosmology: Whether we can rely on a cosmological model to understand the real history of the Universe. This fundamental, still unresolved issue is often called the ``model-fitting problem (or averaging…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Masafumi Seriu

We propose a geometric explanation of the standard model of Glashow, Weinberg and Salam for the known elementary particles. Our model is a generic Quantum Field Theory in dimension four, obtained by developing along a Lorentz sub-manifold…

General Physics · Physics 2016-01-19 Daniel Bennequin

We establish the general conditions under which evolution in the laws of physics and matter creation or destruction are closely intertwined. They make use of global time variables canonically dual to the constants of Nature. Such times flow…

General Relativity and Quantum Cosmology · Physics 2025-02-04 Paolo M Bassani , Joao Magueijo

In cosmology, the cosmic curvature $K$ and the cosmological constant $\Lambda$ are two important parameters, and the values have strong influence on the behavior of the universe. In the context of normal cosmology, under the ordinary…

General Relativity and Quantum Cosmology · Physics 2017-08-11 Ying-Qiu Gu

Light scalar fields very naturally appear in modern cosmological models, affecting such parameters of Standard Model as electromagnetic fine structure constant $\alpha$, dimensionless ratios of electron or quark mass to the QCD scale,…

Atomic Physics · Physics 2009-08-18 V. V. Flambaum , E. V. Shuryak

A new expression to the total age of the Universe is derived in terms of the average deceleration parameter. This kinematic result holds regardless of the curvature of the universe as well as of the underlying gravity theory. It remains…

Astrophysics · Physics 2008-06-11 J. A. S. Lima

In this paper we discuss a possible cosmological time evolution of fundamental constants from the theoretical and experimental point of views. On the theoretical side, we explain that such a cosmological time evolution is actually something…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Xavier Calmet , Matthias Keller

Today, both particle physics and cosmology are described by few parameter Standard Models, i.e. it is possible to deduce consequence of particle physics in cosmology and vice verse. The former is examined in this lecture, in light of the…

High Energy Physics - Phenomenology · Physics 2014-12-05 P. Pralavorio

We study some aspects of cosmologies in 5D models with one infinite extra dimension. Matter is confined to the brane, gravity extends to the bulk. Models with positive and negative tension of the brane are considered. Cosmological evolution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Mikhail Z. Iofa

Universe evolution, as described by Friedmann's equations, is determined by source terms fixed by the choice of pressure $\times$ energy-density equations of state $p(\rho)$. The usual approach in Cosmology considers equations of state…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Aldrovandi , R. R. Cuzinatto , L. G. Medeiros

In a recent paper \cite{Artymowski:2020zwy} we suggested the possibility that the present acceleration of the Universe is due to thermodynamical behavior of unparticles. The model is free of scalar fields, modified gravity, a Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 Michał Artymowski , Ido Ben-Dayan , Utkarsh Kumar

In a unified picture both inflation and present dynamical dark energy arise from the same scalar field. The history of the Universe describes a crossover from a scale invariant "past fixed point" where all particles are massless, to a…

High Energy Physics - Theory · Physics 2015-12-09 C. Wetterich

Our knowledge about the universe has increased tremendously in the last three decades or so --- thanks to the progress in observations --- but our understanding has improved very little. There are several fundamental questions about our…

General Relativity and Quantum Cosmology · Physics 2017-08-22 T. Padmanabhan