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Related papers: Fine-structure constant constraints on dark energy

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Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are becoming an increasingly powerful probe of new physics. Here we discuss how these measurements, combined with local atomic…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 C. J. A. P. Martins , A. M. M. Pinho , R. F. C. Alves , M. Pino , C. I. S. A. Rocha , M. von Wietersheim

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are a powerful probe of new physics. Recently these measurements, combined with local atomic clock tests and Type Ia supernova and…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 C. J. A. P. Martins , A. M. M. Pinho , P. Carreira , A. Gusart , J. López , C. I. S. A. Rocha

We critically assess recent claims suggesting that upper limits on the time variation of the fine-structure constant tightly constrain the coupling of a dark energy scalar field to the electromagnetic sector, and, indirectly, the violation…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 P. P. Avelino

We use recent astrophysical and local tests of the stability of the fine-structure constant, $\alpha$, to constrain a particular phenomenological but physically motivated class of models in which the dark energy equation of state can…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-12 C. J. A. P. Martins , M. Prat Colomer

We investigate a link between the running of the fine structure constant $\alpha$ and a time evolving scalar dark energy field. Employing a versatile parameterization for the equation of state, we exhaustively cover the space of dark energy…

Astrophysics · Physics 2009-11-10 Michael Doran

We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Erminia Calabrese , Eloisa Menegoni , C. J. A. P. Martins , Alessandro Melchiorri , Graca Rocha

There is a growing interest in astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$, as an optimal probe of new physics. The imminent arrival of the ESPRESSO spectrograph…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 C. S. Alves , A. C. O. Leite , C. J. A. P. Martins , T. A. Silva , S. A. Berge , B. S. A. Silva

We show that atomic clock measurements provides an exceptionally sensitive Solar System probe of scalar tensor dark energy. By connecting variations in Newton's constant and differential clock drifts to the dynamics of a single dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-19 Oem Trivedi

It was hypothesized in the literature that some physical parameters may be time-evolving and the astrophysical data can serve as a probe. Recently, James Webb Space Telescope (JWST) have released its early observations. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-15 Ze-Fan Wang , Lei Lei , Lei Feng , Yi-Zhong Fan

Measurements suggest that our universe has a substantial dark energy component. The most recent data on type Ia supernovae give a dark energy density which is in good agreement with other measurements if the dark energy is assumed to be a…

Astrophysics · Physics 2009-11-10 Duane A. Dicus , Wayne W. Repko

We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock frequency comparisons across the network,…

We use the recent type Ia supernova, cosmic microwave background and large-scale structure data to shed light on the temporal evolution of the dark energy equation of state $w(z)$ out to redshift one. We constrain the most flexible…

Astrophysics · Physics 2008-11-26 Gong-Bo Zhao , Dragan Huterer , Xinmin Zhang

Astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, are an optimal probe of new physics. There is a growing interest in these…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-07 A. C. O. Leite , C. J. A. P. Martins

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

We constrain the evolution of the dark energy density from Cosmic Microwave Background, Large Scale Structure and Supernovae Ia measurements. While Supernovae Ia are most sensitive to the equation of state $w_0$ of dark energy today, the…

Astrophysics · Physics 2009-11-13 Michael Doran , Khamphee Karwan , Christof Wetterich

We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

Various classes of exotic singularity models have been studied as possible mimic models for the observed recent acceleration of the universe. Here we further study one of these classes and, under the assumption that they are…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-15 Mariusz P. Dabrowski , Tomasz Denkiewicz , C. J. A. P. Martins , P. E. Vielzeuf

Recent data advances offer the exciting prospect of a first look at whether dark energy has a dynamical equation of state or not. While formally theories exist with a constant equation of state, they are nongeneric -- Einstein's…

Astrophysics · Physics 2009-11-10 Eric V. Linder , Ramon Miquel

We use Hubble parameter versus redshift data from Stern, et al(2010) and Gazta\~{n}aga, et al (2009) to place constraints on model parameters of constant and time-evolving dark energy cosmological models. These constraints are consistent…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-12 Yun Chen , Bharat Ratra

Mapping the behaviour of dark energy is a pressing task for observational cosmology. Phenomenological classification divides dynamical dark energy models into freezing and thawing, depending on whether the dark energy equation of state is…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-11 J. M. A. Vilas Boas , D. M. N. Magano , C. J. A. P. Martins , A. Barbecho , C. Serrano
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