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Related papers: Falsifying Paradigms for Cosmic Acceleration

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We investigate the potential of a future supernova dataset, as might be obtained by the proposed SNAP satellite, to discriminate among different ``dark energy'' theories that describe an accelerating Universe. We find that many such models…

Astrophysics · Physics 2010-04-08 Jochen Weller , Andreas Albrecht

A major recent evelopment in observational cosmology has been an accurate measurement of the luminosity distance-redshift relation out to redshifts z=0.8 from Type Ia supernova standard candles. The results have been argued as evidence for…

Astrophysics · Physics 2016-01-13 Neil Trentham

We analyze the possibility to distinguish between quintessence and phantom scalar field models of dark energy using observations of luminosity distance moduli of SNe Ia, CMB anisotropies and polarization, matter density perturbations and…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-01 B. Novosyadlyj , O. Sergijenko , R. Durrer , V. Pelykh

The dynamics of expansion of the Universe and evolution of scalar perturbations are studied for the quintessential scalar fields $Q$ with the classical Lagrangian satisfying the additional condition $w=const$ or $c^2_a=0$. Both…

Astrophysics · Physics 2009-08-10 B. Novosyadlyj , O. Sergijenko

We study linear power spectra and formation of large scale structures in flat cosmological models with $\Lambda \ge 0$ and cold plus hot dark matter components (MLM). The hot component consists of massive neutrinos with cosmological density…

Astrophysics · Physics 2007-05-23 R. Valdarnini , T. Kahniashvili , B. Novosyadlyj

We consider the weak lensing effect induced by linear cosmological perturbations on the cosmic microwave background (CMB) polarization anisotropies. We find that the amplitude of the lensing peak in the BB mode power spectrum is a faithful…

Astrophysics · Physics 2009-11-13 Viviana Acquaviva , Carlo Baccigalupi

We perform a comprehensive observational test of a canonical quintessence model driven by an exponential potential, motivated by its emergence in higher-dimensional theories, string-inspired scenarios, and modified gravity. Using a Markov…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Sanjeeda Sultana , Surajit Chattopadhyay

We confront the concordance (standard) model of cosmology, the spatially flat $\Lambda$CDM Universe with power-law form of the primordial spectrum with Planck CMB angular power spectrum data searching for possible smooth deviations beyond…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-30 Dhiraj Kumar Hazra , Arman Shafieloo

Dark energy is a fundamental constituent of our universe, its status in the cosmological field equation should be equivalent to that of gravity. Here we construct a dark energy and matter gravity coupling (DEMC) model of cosmology in a way…

General Physics · Physics 2015-01-14 Ti-Pei Li

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

Astrophysics · Physics 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

In the last dozens of years different data sets revealed the accelerated expansion of the Universe which is driven by the so called dark energy, that now dominates the total amount of matter-energy in the Universe. In a recent paper Glavan,…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-27 Marek Demianski , Ester Piedipalumbo

Standard quantum field theory arguments predict an enormous cosmological constant. But what would this mean observationally? For a homogeneous universe the answer is clear, but if the universe is inhomogeneous at the Planck scale, the…

General Relativity and Quantum Cosmology · Physics 2025-10-30 Steven Carlip

The abundance of the most massive objects in the Universe at different epochs is a very sensitive probe of the cosmic background evolution and of the growth history of density perturbations, and could provide a powerful tool to distinguish…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-22 Marco Baldi

In a recent paper we considered the possibility of a scalar field providing an explanation for the cosmic acceleration. Our model had the interesting properties of attractor-like behavior and having its parameters of O(1) in Planck units.…

Astrophysics · Physics 2010-04-08 Constantinos Skordis , Andreas Albrecht

We present a method for calculating large numbers of power spectra C_l and P(k) that accelerates CMBfast by a factor around 10^3 without appreciable loss of accuracy, then apply it to constrain 11 cosmological parameters from current Cosmic…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga , Andrew J. S. Hamilton

The accelerating expansion of the Universe is one of the most surprising and potentially profound discoveries of modern cosmology. Measuring the acceleration well enough to meaningfully constrain interesting physical models requires…

Astrophysics · Physics 2009-11-13 G. Aldering

We present updated constraints on cosmological parameters in a 12-parameter model, extending the standard six-parameter $\Lambda$CDM by including dynamical dark energy (DE: $w_0$, $w_a$), the sum of neutrino masses ($\sum m_{\nu}$), the…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-19 Shouvik Roy Choudhury , Teppei Okumura

Quintessence, a scalar field model, has been proposed to account for the acceleration of the Universe at present. We discuss how accurately quintessence models are discriminated by future cosmological surveys, which include experiments of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Yoshitaka Takeuchi , Kiyotomo Ichiki , Tomo Takahashi , Masahide Yamaguchi

Accounting for large-scale structure in our universe will require not only reasonably accurate mathematical models of its cosmogony, topology and cosmology, but also a more deeper understanding of our fundamental physical concepts of space,…

Astrophysics · Physics 2016-08-30 Charles B. Leffert

The currently available cosmological data yield, as a most striking result, that the expansion rate of the universe seems to be increasing at late times, contrary to the standard (zero cosmological constant) FLRW prediction. The usual…

Astrophysics · Physics 2011-10-31 Marie-Noelle Celerier
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