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Related papers: Linearized Bekenstein Varying Alpha Models

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Astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$, are an area of much increased recent activity, following some indications of possible spacetime variations at the few…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-16 P. M. M. Leal , C. J. A. P. Martins , L. B. Ventura

In a recent paper we demonstrated how the simplest model for varying alpha may be interpreted as the effect of a dielectric material, generalized to be consistent with Lorentz invariance. Unlike normal dielectrics, such a medium cannot…

General Relativity and Quantum Cosmology · Physics 2015-09-03 John D. Barrow , Joao Magueijo

We study the evolution of the fine-structure constant, $\alpha$, induced by non-linear density perturbations in the context of the simplest class of quintessence models with a non-minimal coupling to the electromagnetic field, in which the…

Astrophysics · Physics 2009-11-13 P. P. Avelino , C. J. A. P. Martins , J. Menezes , C. Santos

Recent theoretical ideas and observational claims suggest that the fine structure constant alpha may be variable. We examine a spectrum of models in which alpha is a function of a scalar field. Specifically, we consider three scenarios:…

High Energy Physics - Phenomenology · Physics 2009-11-10 Charles L. Steinhardt

We describe the underlying probabilistic interpretation of alpha and beta divergences. We first show that beta divergences are inherently tied to Tweedie distributions, a particular type of exponential family, known as exponential…

Machine Learning · Statistics 2012-09-20 Y. Kenan Yilmaz , A. Taylan Cemgil

Aims. On the basis the theoretical model proposed by Bekenstein for {\alpha}'s variation, we analyze the equations that describe the energy exchange between matter and both the electromagnetic and the scalar fields. Methods. We determine…

General Relativity and Quantum Cosmology · Physics 2011-04-19 Lucila Kraiselburd , Marcelo Miller Bertolami , Pablo Sisterna , Héctor Vucetich

In this paper, the WKB method is extended to be applicable for conformable Hamiltonian systems where the concept of conformable operator with fractional order $\alpha$ is used. The WKB approximation for the $\alpha$-wavefunction is derived…

Quantum Physics · Physics 2022-09-13 Mohamed. Al-Masaeed , Eqab. M. Rabei , Ahmed Al-Jamel

We introduce a model which allows the fine structure constant (alpha) to vary throughout space and time due to a coupling to a scalar field with a non-canonical kinetic structure. This provided a new extension of the…

General Relativity and Quantum Cosmology · Physics 2015-01-20 Alexander A. H. Graham

The question of whether classically conformal modifications of the standard model are consistent with experimental obervations has recently been subject to renewed interest. The method of Gildener and Weinberg provides a natural framework…

High Energy Physics - Phenomenology · Physics 2019-01-30 Florian Loebbert , Julian Miczajka , Jan Plefka

We compare the classical viscoelastic models due to Becker and Lomnitz with respect to a recent viscoelastic model based on the Lambert W function. We take advantage of this comparison to derive new analytical expressions for the relaxation…

Classical Physics · Physics 2024-11-27 Juan Luis Gonzales Santander , Francesco Mainardi

Three classes of local hidden-variable models that violate both Bell and Leggett inequalities are presented. The models, however, do not reproduce the quantum mechanical predictions, hence they are experimentally testable. It is concluded…

Quantum Physics · Physics 2011-04-25 Antonio Di Lorenzo

We establish sharp inequalities involving the incomplete Beta and Gamma functions. These inequalities arise in the approximation of generalized Bernstein functions by higher order Thorin-Bernstein functions. Furthermore, new properties of a…

Classical Analysis and ODEs · Mathematics 2024-09-05 Stamatis Koumandos , Henrik Laurberg Pedersen

We introduce extension-based proofs, a class of impossibility proofs that includes valency arguments. They are modelled as an interaction between a prover and a protocol. Using proofs based on combinatorial topology, it has been shown that…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-08-04 Dan Alistarh , James Aspnes , Faith Ellen , Rati Gelashvili , Leqi Zhu

We find a strong separation between two natural families of simple rank one theories in Keisler's order: the theories $T_\mathfrak{m}$ reflecting graph sequences, which witness that Keisler's order has the maximum number of classes, and the…

Logic · Mathematics 2023-07-06 M. Malliaris , S. Shelah

We generalize the Bekenstein-Sandvik-Barrow-Magueijo (BSBM) model for the variation of the fine structure 'constant', $\alpha ,$ to include an exponential or inverse power-law self-potential for the scalar field $% \phi $ which drives the…

General Relativity and Quantum Cosmology · Physics 2012-07-04 John D. Barrow , Baojiu Li

$\alpha$-posteriors and their variational approximations distort standard posterior inference by downweighting the likelihood and introducing variational approximation errors. We show that such distortions, if tuned appropriately, reduce…

Machine Learning · Statistics 2021-04-20 Marco Avella Medina , José Luis Montiel Olea , Cynthia Rush , Amilcar Velez

The cosmological evolution of a quintessence-like scalar field, phi, coupled to matter and gauge fields leads to effective modifications of the coupling constants and particle masses over time. We analyze a class of models where the scalar…

Astrophysics · Physics 2009-09-15 Seokcheon Lee , Keith A. Olive , Maxim Pospelov

We put forward an adaptive alpha (Type I Error) that decreases as the information grows, for hypothesis tests in which nested linear models are compared. A less elaborate adaptation was already presented in \citet{PP2014} for comparing…

Methodology · Statistics 2021-01-06 D. Vélez , M. E. Pérez , L. R. Pericchi

The Euler-$\alpha$ equations model the averaged motion of an ideal incompressible fluid when filtering over spatial scales smaller than $\alpha$. We show that there exists $\beta>1$ such that weak solutions to the two and three dimensional…

Analysis of PDEs · Mathematics 2021-11-10 Rajendra Beekie , Matthew Novack

We propose a general model where quintessence couples to electromagnetism via its kinetic term. This novelty generalizes the linear dependence of the gauge kinetic function on $\phi$, commonly adopted in the literature. The interaction…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-23 Bruno J. Barros , Vitor da Fonseca
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