Elliptic CMB Sky

Gurzadyan, V. G.; Bernardis, P. de; Troia, G. De; Bianco, C. L.; Кашин, А. Л.; Kuloghlian, H.; Masi, S.; Polenta, G.; Yegorian, G.

doi:10.1142/s0217732305017111

Cited by 32 publications

(44 citation statements)

References 19 publications

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“…In the present model there are spatial curvature gradients, and we must revisit the calculation from first principles. Volume-average negative spatial curvature, which accords with tests of ellipticity in the CMB anisotropies (Gurzadyan et al 2005(Gurzadyan et al , 2007, can nonetheless be consistent with our local observation of the angular scale of the first peak (Wiltshire 2007a). …”

Section: M0supporting

confidence: 87%

Gravitational Energy as Dark Energy: Concordance of Cosmological Tests

Leith

Wiltshire

2007

ApJ

168

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We provide preliminary quantitative evidence that a new solution to averaging the observed inhomogeneous structure of matter in the universe may lead to an observationally viable cosmology without exotic dark energy. We find parameters which simultaneously satisfy three independent tests: the match to the angular scale of the sound horizon detected in the cosmic microwave background anisotropy spectrum; the effective comoving baryon acoustic oscillation scale detected in galaxy clustering statistics; and Type Ia supernova luminosity distances. Independently of the supernova data, concordance is obtained for a value of the Hubble constant which agrees with the measurement of the and an age of the universe of billion years as measured by observers in galaxies. The mass ratio of ϩ0.714.7 Ϫ0.5 nonbaryonic dark matter to baryonic matter is , computed with a baryon-to-photon ratio that is in con-ϩ2.53.1 Ϫ2.4 cordance with primordial lithium abundances. Subject headings: cosmological parameters -cosmology: observations -cosmology: theory -dark matterlarge-scale structure of universe Online material: color figuresThe apparent acceleration in present cosmic expansion is usually attributed to a smooth "dark energy," whose nature poses a foundational mystery to physics. Our standard LCDM cosmology, with a cosmological constant L as dark energy, fits three independent observational tests: Type Ia supernovae (SNe Ia) luminosity distances; the angular scale of the Doppler peaks in the spectrum of cosmic microwave background (CMB) temperature anisotropies; and the baryon acoustic oscillation scale detected in galaxy clustering statistics. In this Letter we provide preliminary evidence that these same tests can all be satisfied in ordinary general relativity without exotic dark energy, within a model (Wiltshire 2007a(Wiltshire , 2007b which takes a new approach to averaging the observed structure of the universe, presently dominated by voids.Recently a number of cosmologists have questioned whether cosmic acceleration might in fact be an artifact of replacing the actual observed structure of the universe by a smooth featureless dust fluid in Einstein's equations (for a review see Buchert 2007). The specific solution to the averaging problem we investigate here (Wiltshire 2007a) realizes cosmic acceleration as an apparent effect that arises in the decoupling of bound systems from the global expansion of the universe. In particular, gradients in the kinetic energy of expansion, and more importantly, in the quasi-local energy associated with spatial curvature gradients between bound systems and a volume-average position in freely expanding space, can manifest themselves in a significant difference in clock rates between the two locations. This difference is negligible in the early universe when the assumption of homogeneity is valid, but becomes important after the transition to void dominance, making apparent acceleration a phenomenon registered by observers in galaxies at relatively late epochs.Galaxies and other objects...

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Section: M0supporting

confidence: 87%

Gravitational Energy as Dark Energy: Concordance of Cosmological Tests

Leith

Wiltshire

2007

ApJ

168

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“…Previous studies have included non-Gaussianities reported for the CMB properties, such as the multipole alignments, hemisphere anomalies, temperature-independent ellipticity of the excursion sets, large-scale symmetry (see Eriksen et al 2007;Copi et al 2007;Gurzadyan & Torres 1997;Gurzadyan et al 2005Gurzadyan et al , 2007Gurzadyan et al , 2008. Among the signals with low probability at Gaussian fluctuations is a region in the southern sky known as the Cold Spot (Vielva et al 2004;Cruz et al 2005).…”

Section: Introductionmentioning

confidence: 99%

Kolmogorov stochasticity parameter measuring the randomness in the cosmic microwave background

Gurzadyan¹,

Kocharyan

2008

A&A

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The Kolmogorov stochasticity parameter (KSP) is applied to quantify the degree of randomness (stochasticity) in the temperature maps of the Cosmic Microwave Background radiation maps. It is shown that the KSP for the WMAP5 maps is about twice as high as that of the simulated maps for the concordance ΛCDM cosmological model, implying that a randomizing effect exists that has not been taken into account by the model. As was revealed earlier, underdense regions in the large scale matter distributions, i.e. the voids, possess hyperbolic and, hence, randomizing properties. The degree of randomness for the Cold Spot appears to be about twice as high as the average of the mean temperature level spots in the sky, which supports the void nature of the Cold Spot. Kolmogorov's parameter then acts as a quantitative tracer of the voids by means of the CMB.

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“…This is one of the non-Gaussianities among others reported for CMB properties (e.g. de Oliveira-Costa et al 2004;Copi et al 2007;Schwarz et al 2004;Eriksen et al 2004Eriksen et al , 2007Cruz et al 2005Cruz et al , 2009Gurzadyan et al 2005Gurzadyan et al , 2007Morales & Saez 2008).…”

Section: Introductionmentioning

confidence: 50%

Plane-mirroring anomaly in the cosmic microwave background maps

Gurzadyan¹,

Ghahramanyan²,

Кашин³

et al. 2009

A&A

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The plane-mirror symmetry previously noticed in the Cosmic Microwave Background (CMB) temperature anisotropy maps of Wilkinson Microwave Anisotropy Probe is shown to possess certain anomalous properties. The degree of the randomness determined by the Kolmogorov stochasticity parameter in both symmetry regions appears to have identical values which, however, essentially differ from the corresponding values for other sky regions. If the mirroring were of cosmological origin, this would imply either additional randomizing properties in those directions of the Universe or their different line-of-sight depth. This analysis also provides a way to test the hypothesis of a link between the nature of dark energy and inhomogeneities.

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Elliptic CMB Sky

Cited by 32 publications

References 19 publications

Gravitational Energy as Dark Energy: Concordance of Cosmological Tests

Gravitational Energy as Dark Energy: Concordance of Cosmological Tests

Kolmogorov stochasticity parameter measuring the randomness in the cosmic microwave background

Plane-mirroring anomaly in the cosmic microwave background maps

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