English
Related papers

Related papers: Dark energy parameterizations and their effect on …

200 papers

Most parameterizations of the dark energy equation of state do not reflect realistic underlying physical models. Here, we develop a relatively simple description of dark energy based on the dynamics of a scalar field which is exact in the…

Astrophysics · Physics 2008-11-26 Robert Crittenden , Elisabetta Majerotto , Federico Piazza

We develop a formalism to characterize the redshift evolution of the dark energy potential. Our formalism makes use of quantities similar to the Horizon-flow parameters in inflation and is general enough that can deal with multiscalar…

Astrophysics · Physics 2008-11-26 Joan Simon , Licia Verde , Raul Jimenez

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

We use 21 Hubble parameter versus redshift data points, from Gazta\~{n}aga et al. (2009), Stern et al. (2010), and Moresco et al. (2012), to place constraints on model parameters of constant and time-evolving dark energy cosmologies. This…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Omer Farooq , Data Mania , Bharat Ratra

We study the sensitivity of weak lensing by large scale structures to the evolution of dark energy. We explore a 2-parameters model of dark energy evolution, inspired by tracking quintessence models. To this end, we compute the likelihood…

Astrophysics · Physics 2008-11-26 Karim Benabed , Ludovic Van Waerbeke

We analyze time-dependent dark energy equations of state through linear and nonlinear structure formation and their quintessence potentials, characterized by fast, recent transitions, inspired by parameter space studies of selected classes…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-12 Orlando Luongo , Francesco Pace , Sebastiano Tomasi

Time-varying dark energy is often modeled in observational analyses through generic parameterizations of its equation of state $w(z)$, which typically use two free parameters $\{w_0, w_a\}$ to span a broad range of behaviors as a function…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-27 David Shlivko , Paul J. Steinhardt , Charles L. Steinhardt

One of the most important questions nowadays in physics concerns the nature of the so-called dark energy. It is also a consensus among cosmologists that such a question will not be answered on the basis only of observational data. However,…

Astrophysics · Physics 2008-11-26 Deepak Jain , J. S. Alcaniz , Abha Dev

The property of dark energy and the physical reason for acceleration of the present universe are two of the most difficult problems in modern cosmology. The dark energy contributes about two-thirds of the critical density of the present…

Astrophysics · Physics 2009-11-13 F. Y. Wang , Z. G. Dai

Halos of similar mass and redshift exhibit a large degree of variability in their differential properties, such as dark matter, hot gas, and stellar mass density profiles. This variability is an indicator of diversity in the formation…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-20 Arya Farahi , Daisuke Nagai , Dhayaa Anbajagane

In this work, we quantify the cosmological signatures of dark energy radiation -- a novel description of dark energy, which proposes that the dynamical component of dark energy is comprised of a thermal bath of relativistic particles…

High Energy Physics - Phenomenology · Physics 2024-03-27 Kim V. Berghaus , Tanvi Karwal , Vivian Miranda , Thejs Brinckmann

I review the observational prospects to constrain the equation of state parameter of dark energy and I discuss the potential of future imaging and redshift surveys. Bayesian model selection is used to address the question of the level of…

Astrophysics · Physics 2007-05-23 Roberto Trotta

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Ivan de Martino

A new class of neutrino dark energy models is presented. The new models are characterized by the lack of exotic particles or couplings that violate the standard model symmetry. It is shown that these models lead to several concrete…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Ilya Gurwich

Aims. We investigate the degree of improvement in dark energy constraints that can be achieved by extending Type Ia Supernova (SN Ia) samples to redshifts z > 1.5 with the Hubble Space Telescope (HST), particularly in the ongoing CANDELS…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-10 Vincenzo Salzano , Steven A. Rodney , Irene Sendra , Ruth Lazkoz , Adam G. Riess , Marc Postman , Tom Broadhurst , Dan Coe

The annihilation of dark matter particles releases energy, ionizing some of the gas in the Universe. We investigate the effect of dark matter halos on reionization. We show that the effect depends on the assumed density profile, the…

Astrophysics · Physics 2014-11-18 Aravind Natarajan , Dominik J. Schwarz

Detecting dark energy dynamics is the main quest of current dark energy research. Addressing the issue demands a fully consistent analysis of CMB, large scale structure and SN-Ia data with multi-parameter freedom valid for all redshifts.…

Astrophysics · Physics 2008-11-26 P. S. Corasaniti , M. Kunz , D. Parkinson , E. J. Copeland , B. A. Bassett

We present here some recent results concerning scalar-tensor Dark Energy models. These models are very interesting in many respects: they allow for a consistent phantom phase, the growth of matter perturbations is modified. Using a…

Astrophysics · Physics 2016-11-15 R. Gannouji , D. Polarski , A. Ranquet , A. A. Starobinsky

We examine the effect of inhomogeneous reionization on the galaxy power spectrum and the consequences for probing dark energy. To model feedback during reionization, we apply an ansatz setting the galaxy overdensity proportional to the…

Astrophysics · Physics 2008-11-26 Jonathan R. Pritchard , Steven R. Furlanetto , Marc Kamionkowski

The dependence of Hubble parameter on redshift can be determined directly from the dipole of luminosity distance to Supernovae Ia. We investigate the possibility of using the data on dipole of the luminosity distance obtained from the…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-06 O. Sergijenko