Inhomogeneous alternative to dark energy

  title={Inhomogeneous alternative to dark energy},
  author={H̊avard Alnes and Morad Amarzguioui and Oyvind G Gron},
  journal={Physical Review D},
Recently, there have been suggestions that the apparent accelerated expansion of the universe is not caused by repulsive gravitation due to dark energy, but is rather a result of inhomogeneities in the distribution of matter. In this work, we investigate the behavior of a dust-dominated inhomogeneous Lema\^{\i}tre-Tolman-Bondi universe model, and confront it with various astrophysical observations. We find that such a model can easily explain the observed luminosity distance-redshift relation… Expand
Is the evidence for dark energy secure?
Several kinds of astronomical observations, interpreted in the framework of the standard Friedmann–Robertson–Walker cosmology, have indicated that our universe is dominated by a CosmologicalExpand
Dark energy as a mirage
Motivated by the observed cosmic matter distribution, we present the following conjecture: due to the formation of voids and opaque structures, the average matter density on the path of the lightExpand
The cosmic microwave background in an inhomogeneous universe
The dimming of Type Ia supernovae could be the result of Hubble-scale inhomogeneity in the matter and spatial curvature, rather than signaling the presence of a dark energy component. A key challengeExpand
Reconciling the local void with the CMB
In the standard cosmological model, the dimming of distant Type Ia supernovae is explained by invoking the existence of repulsive ''dark energy'' which is causing the Hubble expansion to accelerate.Expand
Can the cosmological constant be mimicked by smooth large-scale inhomogeneities for more than one observable?
As an alternative to dark energy it has been suggested that we may be at the center of an inhomogeneous isotropic universe described by a Lemaitre-Tolman-Bondi (LTB) solution of Einstein's fieldExpand
Challenging dark energy with exact inhomogeneous models
The dimming of the SN Ia apparent luminosity is generally ascribed to the influence of a “dark energy” component, which is supposed to yield a late-time acceleration of the Universe expansion rate.Expand
Conceptual problems in detecting the evolution of dark energy when using distance measurements
Dark energy is now one of the most important and topical problems in cosmology. The first step to reveal its nature is to detect the evolution of dark energy or to prove beyond doubt that theExpand
Rendering dark energy void
Dark energy observations may be explained within general relativity using an inhomogeneous Hubble-scale depression in the matter density and accompanying curvature, which evolves naturally out of anExpand
Supernova hubble diagram for off-center observers in a spherically symmetric inhomogeneous universe
We have previously shown that spherically symmetric, inhomogeneous universe models can explain both the supernova data and the location of the first peak in the spectrum of the cosmic microwaveExpand
Backreaction of inhomogeneities can mimic dark energy
In the standard approach to cosmology, the evolution and observations associated with an inhomogeneous universe with density p(x) are modeled by employing a homogeneous cosmological model of densityExpand


Cosmic microwave background, accelerating Universe and inhomogeneous cosmology
We consider a cosmology in which a spherically symmetric large scale inhomogeneous enhancement or a void are described by an inhomogeneous metric and Einstein's gravitational equations. For a flatExpand
An alternative to the cosmological 'concordance model'
Precision measurements of the cosmic microwave background by WMAP are believed to have established a flat $\Lambda$-dominated universe, seeded by nearly scale-invariant adiabatic primordialExpand
Can the acceleration of our universe be explained by the effects of inhomogeneities
No, it is simply not plausible that cosmic acceleration could arise within the context of general relativity from a back-reaction effect of inhomogeneities in our universe, without the presence of aExpand
Do we really see a cosmological constant in the supernovae data
The magnitude-redshift relation is one of the tools for a direct observational approach to cosmology. The discovery of high redshift Type Ia supernovae (SNIa) and their use as “standard candles” hasExpand
Effect of Inhomogeneity on Cosmological Models.
  • R. Tolman
  • Physics, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 1934
It is evident that some preponderating tendency for inhomogeneities to disappear with time would have to be demonstrated, before homogeneous models could be used with confidence to obtain extrapolated conclusions as to the behavior of the universe in very distant regions or over exceedingly long periods of time. Expand
Bulk Flows and Cosmic Microwave Background Dipole Anisotropy in Cosmological Void Models
The observational behavior of spherically symmetric inhomogeneous cosmological models is studied, which consist of inner and outer homogeneous regions connected by a shell or an intermediateExpand
Do large-scale inhomogeneities explain away dark energy?
Recently, new arguments [E. Barausse, S. Matarrese, and A. Riotto, Phys. Rev. D 71, 063537 (2005).][E. W. Kolb, S. Matarrese, A. Notari, and A. Riotto, hep-th/0503117 [Phys. Rev. Lett. (to beExpand
Can superhorizon cosmological perturbations explain the acceleration of the Universe
We investigate the recent suggestions by Barausse et al. and Kolb et al. that the acceleration of the universe could be explained by large superhorizon fluctuations generated by inflation. We showExpand
Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
We present spectral and photometric observations of 10 Type Ia supernovae (SNe Ia) in the redshift range 0.16 " z " 0.62. The luminosity distances of these objects are determined by methods thatExpand
We present spectral and photometric observations of 10 Type Ia supernovae (SNe Ia) in the redshift range 0.16 " z " 0.62. The luminosity distances of these objects are determined by methods thatExpand