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Related papers: The time variation of the fine structure constant:…

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A number of positive and null results on the time variation of fundamental constants have been reported. It is difficult to judge whether or not these claims are mutually consistent, since the observable quantities depend on several…

High Energy Physics - Phenomenology · Physics 2009-02-23 Thomas Dent , Steffen Stern , Christof Wetterich

The next decade of survey astronomy has the potential to transform our knowledge of variable stars. Stellar variability underpins our knowledge of the cosmological distance ladder, and provides direct tests of stellar formation and…

Astrophysical indications that the fine structure constant has undergone a small time variation during the cosmological evolution are discussed within the framework of the standard model of the electroweak and strong interactions and of…

High Energy Physics - Phenomenology · Physics 2009-11-07 H. Fritzsch

In many astrophysical systems, smoothly-varying large-scale variations coexist with small-scale fluctuations. For example, a large-scale velocity or density gradient can exist in molecular clouds that exhibit small-scale turbulence. In…

Instrumentation and Methods for Astrophysics · Physics 2017-10-20 Jungyeon Cho

If the reported measurements of the time variation of the fine structure constant from observations of distant QSOs are correct, combined with the Oklo limit they would strongly constrain the class of the quintessence potential. If these…

High Energy Physics - Phenomenology · Physics 2009-11-07 Takeshi Chiba , Kazunori Kohri

In a recent publication [Ferreira {\it et al.}, Phys. Rev. D89 (2014) 083011] we tested the consistency of current astrophysical tests of the stability of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. C. Ferreira , C. J. A. P. Martins

The tests of the constancy of the fundamental constants are tests of the local position invariance and thus of the equivalence principle. We summarize the various constraints that have been obtained and then describe the connection between…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Jean-Philippe Uzan

Astronomical observations have a unique ability to determine the laws of physics at distant times in the universe. They, therefore, have particular relevance in answering the basic question as to whether the laws of physics are invariant…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-11 Rodger I. Thompson

We discuss how laboratory experiments can be used to place constraints on possible variations of the fine structure constant alpha in the observationally relevant redshift interval z ~= 0 - 5, within a rather general theoretical framework.…

Astrophysics · Physics 2009-10-30 Mario Livio , Massimo Stiavelli

In the analysis of variable stars, the problem of sampling is central. This article focusses on the determination of the Nyquist frequency. It is well defined in the case of regular sampling. However, the time series of variable stars…

Astrophysics · Physics 2009-10-30 L. Eyer , P. Bartholdi

We review properties of cosmological theories for the variation of the fine structure 'constant'. We highlight some general features of the cosmological models that exist in these theories with reference to recent quasar data that are…

General Relativity and Quantum Cosmology · Physics 2012-12-11 John D. Barrow

In this paper we provide a flexible framework allowing for a unified study of time consistency of risk measures and performance measures (also known as acceptability indices). The proposed framework not only integrates existing forms of…

Probability · Mathematics 2017-09-08 Tomasz R. Bielecki , Igor Cialenco , Marcin Pitera

On the basis of an analysis of previous research, we present a generalized approach for measuring the difference of plans with an exemplary application to machine scheduling. Our work is motivated by the need for such measures, which are…

Artificial Intelligence · Computer Science 2015-03-17 Martin Josef Geiger

If the fine structure constant is not really constant, is this due to a variation of $e$, $\hbar$, or $c$? It is argued that the only reasonable conclusion is a variable speed of light.

Quantum Physics · Physics 2009-11-07 Asher Peres

Dependence of transition frequencies on the fine structure constant $\alpha=e^2/\hbar c$ is calculated for several many-electron systems which are used or planned to be used in the laboratory search for the time variation of the fine…

Atomic Physics · Physics 2009-11-13 V. A. Dzuba , V. V. Flambaum

Estimation of structure, such as in variable selection, graphical modelling or cluster analysis is notoriously difficult, especially for high-dimensional data. We introduce stability selection. It is based on subsampling in combination with…

Methodology · Statistics 2009-05-16 Nicolai Meinshausen , Peter Buehlmann

In this paper we compare the dimensional method with the Lie groups tactic in order to show the limitations and advantages of each technique. For this purpose we study in detail a perfect fluid cosmological model with time-varying…

General Relativity and Quantum Cosmology · Physics 2009-09-29 José Antonio Belinchón

The idea of possible time or space variations of the `fundamental' constants of nature, although not new, is only now beginning to be actively considered by large numbers of researchers in the particle physics, cosmology and astrophysics…

Astrophysics · Physics 2009-11-07 C. J. A. P. Martins

We show that if one or more of the `constants' of Nature can vary then their values, as measured in the laboratory, should oscillate over the year in a very particular way. These seasonal changes in the constants could well be detected, in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Douglas J. Shaw

Review of recent works devoted to the temporal and spatial variation of the fundamental constants and dependence of the fundamental constants on the gravitational potential (violation of local position invariance) is presented. We discuss…

Nuclear Theory · Physics 2009-08-18 V. V. Flambaum
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