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The possibility of reconstructing the dark energy equation of state from variations in the fine structure constant is investigated for a class of models where the quintessence field is non-minimally coupled to the electromagnetic field. For…

Astrophysics · Physics 2009-11-10 N. J. Nunes , James E. Lidsey

I review the theoretical motivation for varying fundamental couplings and discuss how these measurements can be used to constrain a number of fundamental physics scenarios that would otherwise be inacessible to experiment. As a case study I…

Astrophysics · Physics 2015-06-24 C. J. A. P. Martins

We discuss methods based on Principal Component Analysis to constrain the dark energy equation of state using a combination of Type Ia supernovae at low redshift and spectroscopic measurements of varying fundamental couplings at higher…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 L. Amendola , A. C. O. Leite , C. J. A. P. Martins , N. J. Nunes , P. O. J. Pedrosa , A. Seganti

We assess the viability of successful reconstruction of the evolution of the dark energy equation of state using varying fundamental couplings, such as the fine structure constant or the proton-to-electron mass ratio. We show that the same…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 P. P. Avelino , L. Losano , R. Menezes , J. C. R. E. Oliveira

In previous work [Amendola {\it et al.}, Phys. Rev. D86 (2012) 063515], Principal Component Analysis based methods to constrain the dark energy equation of state using Type Ia supernovae and other low redshift probes were extended to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-22 A. C. O. Leite , C. J. A. P. Martins

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

The understanding of the accelerated expansion of the Universe poses one of the most fundamental questions in physics and cosmology today. Whether or not the acceleration is driven by some form of dark energy, and in the absence of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Piedipalumbo , E. Della Moglie , M. De Laurentis , P. Scudellaro

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

We investigate the equation of state w(z) in a non-parametric form using the latest compilations of distance luminosity from SNe Ia at high z. We combine the inverse problem approach with a Monte Carlo to scan the space of priors. On the…

Astrophysics · Physics 2010-04-23 Cristina Espana-Bonet , Pilar Ruiz-Lapuente

The variation of dark energy density with redshift, $\rho_X(z)$, provides a critical clue to the nature of dark energy. Since $\rho_X(z)$ depends on the dark energy equation of state $w_X(z)$ through an integral, $\rho_X(z)$ can be…

Astrophysics · Physics 2009-11-10 Yun Wang , Katherine Freese

We investigate how precisely we can determine the nature of dark energy such as the equation of state (EoS) and its time dependence by using future observations of 21 cm fluctuations at the epoch of reionization (6.8 <~ z <~ 10) such as…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-07 Kazunori Kohri , Yoshihiko Oyama , Toyokazu Sekiguchi , Tomo Takahashi

In this paper we study the impact of the fractional matter density uncertainty in the reconstruction of the equation of state of dark energy. We consider both standard reconstruction methods, based on the dynamical effect that dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 P. P. Avelino

New techniques based on weak measurements have recently been introduced to the field of quantum state reconstruction. Some of them allow the direct measurement of each matrix element of an unknown density operator and need only $O(d)$…

Quantum Physics · Physics 2019-01-31 Luca Calderaro , Giulio Foletto , Daniele Dequal , Paolo Villoresi , Giuseppe Vallone

Precision measurements of nature's fundamental couplings and a first measurement of the cosmological redshift drift are two of the key targets for future high-resolution ultra-stable spectrographs such as CODEX. Being able to do both gives…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 P. E. Vielzeuf , C. J. A. P. Martins

We adopt a model independent method to reconstruct the dark energy equation of state by analyzing 5 sets of SNe Ia data along with Baryon Acoustic Oscillation (BAO) and Observational Hubble Data (OHD). The SNe Ia data sets include the most…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-15 Debabrata Adak , Abhijit Bandyopadhyay , Debasish Majumdar

We examine the properties of dark energy and dark matter through the study of the variation of the electromagnetic coupling. For concreteness, we consider the unification model of dark energy and dark matter, the generalized Chaplygin gas…

Astrophysics · Physics 2008-11-26 M. C. Bento , O. Bertolami , P. Torres

The main aim of this paper is to perform a model comparison for some reconstructions of the key properties that describe the dark energy of the Universe i.e. energy density and the equation of state (EoS). We carry out this process by using…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-28 Luis A. Escamilla , J. Alberto Vazquez

The coupling between the dark components provides a new approach to mitigate the coincidence problem of cosmological standard model. In this paper, dark energy is treated as a fluid with a constant equation of state, whose coupling with…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-18 Weiqiang Yang , Lixin Xu

We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Omega_m]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Plionis , R. Terlevich , S. Basilakos , F. Bresolin , E. Terlevich , J. Melnick , R. Chavez

An important issue in cosmology is reconstructing the effective dark energy equation of state directly from observations. With so few physically motivated models, future dark energy studies cannot only be based on constraining a dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Chris Clarkson , Caroline Zunckel
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