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Related papers: Probing Dark Energy through Scale Dependence

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The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…

Astrophysics · Physics 2009-11-13 Urbano Franca

The weak gravitational lensing of distant galaxies by large-scale structure is expected to become a powerful probe of dark energy. By measuring the ellipticities of large numbers of background galaxies, the subtle gravitational distortion…

Astrophysics · Physics 2014-11-18 Charles Shapiro

We study the evolution of galaxy clustering in various cosmological models with quintessence. We investigate how the analytical predictions vary with change of dark energy equation of state $w_X$. Comparing these predictions against…

Astrophysics · Physics 2015-06-24 Dipak Munshi , Cristiano Porciani , Yun Wang

We study a dark energy model with non-zero anisotropic stress, either linked to the dark energy density or to the dark matter density. We compute approximate solutions that allow to characterise the behaviour of the dark energy model and to…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Wilmar Cardona , Lukas Hollenstein , Martin Kunz

Analyses of upcoming galaxy surveys will require careful modelling of relevant observables such as the power spectrum of galaxy counts in harmonic space $C_\ell(z,z')$. We investigate the impact of disregarding relevant relativistic effects…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-28 Wilmar Cardona , Rubén Arjona , Savvas Nesseris

Understanding of the nature of dark energy, which appears to drive the expansion of the universe, is one of the central problems of physical cosmology today. In an earlier paper [Daly & Djorgovski (2003)] we proposed a novel method to…

Astrophysics · Physics 2009-11-10 Ruth A. Daly , S. G. Djorgovski

Any theory invoked to explain cosmic acceleration predicts consistency relations between the expansion history, structure growth, and all related observables. Currently there exist high-quality measurements of the expansion history from…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 R. Ali Vanderveld , Michael J. Mortonson , Wayne Hu , Tim Eifler

The nature of dark energy is a mystery to us. This paper uses the supernova data to explore the property of dark energy by some model independent methods. We first Talyor expanded the scale factor $a(t)$ to find out the deceleration…

Astrophysics · Physics 2009-09-29 Yungui Gong

Many ambitious experiments have been proposed to constrain dark energy and detect its evolution. At present, observational constraints are consistent with a cosmological constant and there is no firm evidence for any evolution in the dark…

Astrophysics · Physics 2009-02-26 Sirichai Chongchitnan , George Efstathiou

We propose a new class of metastable dark energy (DE) phenomenological models in which the DE decay rate does not depend on external parameters such as the scale factor or the curvature of the Universe. Instead, the DE decay rate is assumed…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-23 Arman Shafieloo , Dhiraj Kumar Hazra , Varun Sahni , Alexei A. Starobinsky

Dark energy is often assumed to be composed by a single scalar field. The background cosmic expansion is not sufficient to determine whether this is true or not. We study multi-field scalar-tensor models with a general dark matter source…

General Relativity and Quantum Cosmology · Physics 2015-07-15 Valeri Vardanyan , Luca Amendola

We explore the possibility that the dark energy is due to a potential of a scalar field and that the magnitude and the slope of this potential in our part of the universe are largely determined by anthropic selection effects. We find that,…

High Energy Physics - Theory · Physics 2009-09-29 Jaume Garriga , Andrei Linde , Alexander Vilenkin

We review the ability of redshift surveys to provide constraints on the Dark Energy content of the Universe. The matter power spectrum and dynamics at the present epoch are nearly `blind' to Dark Energy, but combined with the CMB they can…

Astrophysics · Physics 2007-05-23 Ofer Lahav

The ability to test the nature of dark mass-energy components in the universe through large-scale structure studies hinges on accurate predictions of sky survey expectations within a given world model. Numerical simulations predict key…

Within the framework of spatially covariant theories, we propose a general model for dark energy (DE) in which the cosmological background and perturbations are independently controlled by different sets of coefficients, and the equation of…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Zhibang Yao , Gen Ye , Alessandra Silvestri

We apply the Lagrangian perturbation theory with time-dependent growth functions at second and third order of perturbation with the aim to model the effect of dynamical dark energy on redshift-space distortions. Our fiducial galaxy redshift…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Chakkrit Kaeonikhom , Teeraparb Chantavat

The amount and nature of dark energy (DE) can be tightly constrained by measuring the spatial correlation features and evolution of a sample of ~ 100,000 galaxy clusters over the redshift range 0<z < 1.5. Such an X-ray survey will discover…

Cosmology in the near future promises a measurement of the sum of neutrino masses, a fundamental Standard Model parameter, as well as substantially-improved constraints on the dark energy. We use the shape of the BOSS redshift-space galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-09 Amol Upadhye

Cosmic acceleration is widely believed to require either a source of negative pressure (i.e., dark energy), or a modification of gravity, which necessarily implies new degrees of freedom beyond those of Einstein gravity. In this paper we…

High Energy Physics - Theory · Physics 2017-06-28 Lasha Berezhiani , Justin Khoury , Junpu Wang

We detail a novel theoretical prediction that a geometric torsion model for scalar field dark matter could lead to oscillations, on readily probeable timescales, in the time evolution of cosmological redshifts of astronomical sources with…

General Relativity and Quantum Cosmology · Physics 2023-02-20 James Wheeler
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