Constraining the dark energy and smoothness-parameter with supernovae

Abstract

The presence of inhomogeneities modifies the cosmic distances through the gravitational lensing effect, and, indirectly, must affect the main cosmological tests. Assuming that the dark energy is a smooth component, the simplest way to account for the influence of clustering is to suppose that the average evolution of the expanding Universe is governed by the total matter-energy density whereas the focusing of light is only affected by a fraction of the total matter density quantified by the $\alpha$ Dyer-Roeder parameter. By using two different samples of SNe type Ia data, the ${\Omega }_m$ and $\alpha$ parameters are constrained by applying the Zeldovich-Kantowski-Dyer-Roeder (ZKDR) luminosity distance redshift relation for a flat ($\Lambda$CDM) model. A ${\chi }^2$-analysis using the 115 SNe Ia data of Astier {\it et al.} sample (2006) constrains the density parameter to be ${\Omega }_m=0.26_{-0.07}^{+0.17}$($2\sigma$) while the $\alpha$ parameter is weakly limited (all the values $\in [0,1]$ are allowed even at 1$\sigma$). However, a similar analysis based the 182 SNe Ia data of Riess {\it et al.} (2007) constrains the pair of parameters to be ${\Omega }_m=0.33_{-0.07}^{+0.09}$ and $\alpha \ge 0.42$ ($2\sigma$). Basically, this occurs because the Riess {\it et al.} sample extends to appreciably higher redshifts. As a general result, even considering the existence of inhomogeneities as described by the smoothness $\alpha$ parameter, the Einstein-de Sitter model is ruled out by the two samples with a high degree of statistical confidence ($11.5\sigma$ and $9.9\sigma$, respectively). The inhomogeneous Hubble-Sandage diagram discussed here highlight the necessity of the dark energy, and a transition deceleration/accelerating phase at $z\sim 0.5$ is also required.

6 pages, 8 figures, typos corrected, paper matching the version published in Physical Review D

References in corpus (64)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• The Cosmological Constant and Dark Energy
• Cosmological Constant - the Weight of the Vacuum
• Discovery of a Supernova Explosion at Half the Age of the Universe and its Cosmological Implications
• The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set
• New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
• Dark Energy Constraints from the Cosmic Age and Supernova
• Reconstructing Dark Energy
• Evolution of the Scale Factor with a Variable Cosmological Term
• Dark Energy: Vacuum Fluctuations, the Effective Phantom Phase, and Holography
• Is There A Cosmological Constant?
• Nonminimal coupling and quintessence
• A theoretician's analysis of the supernova data and the limitations in determining the nature of dark energy
• Cosmological parameters from supernova observations: A critical comparison of three data sets
• New dark energy constraints from supernovae, microwave background and galaxy clustering
• A comparison of cosmological models using recent supernova data
• Gravitational Lensing as a Probe of Quintessence
• Limits on Cosmological Models From Radio-Selected Gravitational Lenses
• Smoothing Supernova Data to Reconstruct the Expansion History of the Universe and its Age
• Running G and Λat low energies from physics at M_X: possible cosmological and astrophysical implications
• What Do Gravitational Lens Time Delays Measure?
• Thermodynamics of Decaying Vacuum Cosmologies
• Consequences on variable Lambda-models from distant Type Ia supernovae and compact radio sources
• Decaying Vacuum Energy and Deflationary Cosmology in Open and Closed Universes
• Interpreting Cosmological Vacuum Decay
• The Evolution and Structure of Early-type Field Galaxies: A Combined Statistical Analysis of Gravitational Lenses
• Exploring Cosmological Expansion Parametrizations with the Gold SnIa Dataset
• A study of the angular size-redshift relation for models in which $\Lambda$ decays as the energy density
• Constraining Dark Energy with X-ray Galaxy Clusters, Supernovae and the Cosmic Microwave Background
• Expected constraints on the generalized Chaplygin equation of state from future supernova experiments and gravitational lensing statistics
• Alternative Dark Energy Models: An Overview
• Thermodynamics, Spectral Distribution and the Nature of Dark Energy
• Model Independent Reconstruction of the Expansion History of the Universe and the Properties of Dark Energy
• Constraining the dark energy with galaxy clusters X-ray data
• Scalar-field-dominated cosmology with a transient accelerating phase
• Constraining the cosmic equation of state from old galaxies at high redshift
• Cosmological constraints on Chaplygin gas dark energy from galaxy clusters X-ray and supernova data
• The Effects of Inhomogeneities on Evaluating the mass parameter ${\Omega }_m$ and the cosmological constant $\Lambda$
• Constraints on Cardassian Expansion from Distant type Ia Supernovae
• Study of the Magnitude-Redshift Relation for type Ia Supernovae in a Model resulting from a Ricci-Symmetry
• Generalized Chen-Wu type cosmological model
• An old quasar in a young dark energy-dominated universe?
• On the Stability of Phantom K-essence Theories
• Decaying Lambda cosmology, varying G and holography
• Decaying $\Lambda$ cosmologies and statistical properties of gravitational lenses
• New Constraints from High Redshift Supernovae and Lensing Statistics upon Scalar Field Cosmologies
• The Existence of an Old Quasar at $z=3.91$ and its Implications for $\Lambda (t)$ Deflationary Cosmologies
• Scalar field description of decaying-$\Lambda$ cosmologies
• Bayesian Analysis of the (Generalized) Chaplygin Gas and Cosmological Constant Models using the 157 gold SNe Ia Data
• Cosmological constraints from lensing statistics and supernovae on the cosmic equation of state
• A Simple Method To Find All Lensed Quasars
• Distances in inhomogeneous quintessence cosmology
• Approximate angular diameter distance in a locally inhomogeneous universe with nonzero cosmological constant
• Causal Bulk Viscous Dissipative Isotropic Cosmologies with Variable Gravitational and Cosmological Constants
• The Lame${}^{\prime }$ Equation for Distance-Redshift in Partially Filled Beam Friedmann-Lema\^ıtre-Robertson-Walker Cosmology
• Transition from Clumpy to Smooth Angular Diameter Distances
• New Constraints on the Variable Equation of State Parameter from X-Ray Gas Mass Fractions and SNe Ia
• Matter fields from a decaying background Lambda vacuum
• An investigation of gravitational lens determinations of H_o in quintessence cosmologies
• The Dyer-Roeder distance in quintessence cosmology and the estimation of H_0 through time-delays
• The Dyer-Roeder relation in a universe with particle production
• Minimal Angular Size of Distant Sources in Open, $\Lambda$CDM, and Scalar Field Cosmologies

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• CDM Accelerating Cosmology as an Alternative to LCDM model
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