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Related papers: An asymptotic decrease of (m_p/m_e) with cosmologi…

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The possible small variation downward by about $10^{-5}$, of the ratio of the proton mass to the electron mass, over cosmological time is related to the decrease with time of a small vacuum expectation value for a Goldstone-like…

Astrophysics · Physics 2007-07-17 Saul Barshay , Georg Kreyerhoff

We consider a small, metastable maximum vacuum expectation value $b_0$ of order of a few eV, for a pseudoscalar Goldstone-like field, which is related to the scalar inflaton field $\phi$ in an idealized model of a cosmological,…

Astrophysics · Physics 2009-06-23 Saul Barshay , Georg Kreyerhoff

Motivated by recent astrophysical observations of quasar absorption systems, we formulate a simple theory where the electron to proton mass ratio $\mu =m_{e}/m_{p}$ is allowed to vary in space-time. In such a minimal theory only the…

Astrophysics · Physics 2009-11-10 John D Barrow , Joao Magueijo

Multidimensional cosmologies allow for variations of fundamental physical constants over the course of cosmological evolution, and different versions of the theories predict different time dependences. In particular, such variations could…

We report new upper limits on any possible long-term time variation of the ratio of the electron to proton masses, $(m_e/m_p)$, the fine-structure constant, ($\alpha$), and the quantity $\alpha^2 g_p(m_e/m_p)$, where $g_p$ is the proton…

Astrophysics · Physics 2011-07-18 Lennox L. Cowie , Antoinette Songaila

We estimate the cosmological variation of the proton-to-electron mass ratio \mu=m_p/m_e by measuring the wavelengths of molecular hydrogen transitions in the early universe. The analysis is performed using high spectral resolution…

Astrophysics · Physics 2009-11-07 A. Ivanchik , E. Rodriguez , P. Petitjean , D. Varshalovich

We will look for an implementation of new symmetries in the space-time structure and their cosmological implications. This search will allow us to find a unified vision for electrodynamics and gravitation. We will attempt to develop a…

General Physics · Physics 2011-11-10 Claudio Nassif

Exotic cosmologies predict variability of the fundamental physical constants over the cosmic time. Using the VLT/UVES high resolution spectra of the quasar Q0347-3819 and unblended electronic - vibrational - rotational lines of the H2…

Astrophysics · Physics 2014-10-13 S. A. Levshakov , M. Dessauges-Zavadsky , S. D'Odorico , P. Molaro

The model of low-energy quantum gravity by the author has the property of asymptotic freedom at very short distances. The character of transition to asymptotic freedom is studied here. It is shown that this transition is not universal, but…

High Energy Physics - Theory · Physics 2008-03-14 Michael A. Ivanov

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

Astrophysics · Physics 2010-12-17 Antonio F. Rañada

In this paper we point out that the radius R, the age t and the mass M of the observable Universe are proportional to Planck units for length lp, time tp and mass mp.This hypothesis is related, by a cosmological model linking the universal…

Astrophysics · Physics 2007-05-23 Juan Casado Gimenez

The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the…

Astrophysics · Physics 2009-08-18 Michael T. Murphy , Victor V. Flambaum , Sebastien Muller , Christian Henkel

The evidence for the accelerated expansion of the universe and the time-dependence of the fine-structure constant suggests the existence of at least one scalar field with a mass of order H_0. If such a field exists, then it is generally…

Astrophysics · Physics 2009-11-10 Justin Khoury , Amanda Weltman

We discuss models in which the smallness of the effective vacuum energy density $\rho_\L$ and the coincidence of the time of its dominance $t_\L$ with the epoch of galaxy formation $t_G$ are due to anthropic selection effects. In such…

Astrophysics · Physics 2009-10-31 Jaume Garriga , Alexander Vilenkin

We summarize and explain the current status of time variations of the electron mass in cosmology, showing that such variations allow for significant easing of the Hubble tension, from the current $\sim5\sigma$ significance, down to between…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Nils Schöneberg , Léo Vacher

Spacetime variations of physical constants can be associated with the existence of Higgs-like scalar field(s) that couple non-universally to the baryonic matter. Recent results of astronomical spectral measurements of the fractional changes…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 S. A. Levshakov

We study the time variation of fundamental constants in the early Universe. Using data from primordial light nuclei abundances, CMB and the 2dFGRS power spectrum, we put constraints on the time variation of the fine structure constant…

In this work a satisfactory, simple theoretical prediction of the data corresponding to observationally (by fine tuning condition) estimated value of the cosmological constant is given. It is supposed (in conceptually analogy with…

Astrophysics · Physics 2007-12-27 Vladan Pankovic , Simo Ciganovic , Jovan Ivanovic , Rade Glavatovic , Petar Grujic

A short review about vacuum energy and the cosmological constant is presented. The observed acceleration of the universe introduces a new meV energy scale. The problem is that, theoretically, the predicted vacuum energy is many orders of…

High Energy Physics - Theory · Physics 2009-09-01 Eduard Masso

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
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