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Related papers: COBE Constraints on Baryon Isocurvature Models

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We determine the range of parameter space of Interacting Quintessence Models that best fits the recent WMAP measurements of Cosmic Microwave Background temperature anisotropies. We only consider cosmological models with zero spatial…

Astrophysics · Physics 2009-11-10 German Olivares , Fernando Atrio-Barandela , Diego Pavon

We show that the difference between the theoretically expected and measured by WMAP amplitude of the quadrupole fluctuations of CMB can be related to the impact of the anisotropic curvature of the homogeneous universe dominated by the dark…

Astrophysics · Physics 2008-11-26 M. Demiański , A. G. Doroshkevich

We compute the joint constraints on ten cosmological parameters from the latest CMB measurements. The lack of a significant second acoustic peak in the latest Boomerang and Maxima data favors models with more baryons than Big Bang…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga

Cosmic microwave background anisotropies encode crucial information about the early Universe and fundamental cosmological physics. Although the standard $\Lambda$CDM model provides a successful description of cosmic evolution, persistent…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-05 Yang Han , Lu Chen , Guo-Hao Li , Pei-Yuan Xu

It is often assumed that primordial perturbations are statistically isotropic, which implies, among other properties, that their power spectrum is invariant under rotations. In this article, we test this assumption by placing…

Astrophysics · Physics 2009-02-23 C. Armendariz-Picon , Larne Pekowsky

We review the constraints on baryon inhomogeneities derived from measurements of the deuterium abundance, $D/H$, and apply them to a range of baryogenesis models. In particular, we derive bounds on electroweak baryogenesis as well as on…

High Energy Physics - Phenomenology · Physics 2026-04-14 Aleksandr Azatov , Bruno Missoni

We discuss what can be learned about the baryon density from an all-sky map of the cosmic microwave background (CMB) with sub-degree angular resolution. With only minimal assumptions about the primordial spectrum of density perturbations…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski , Gerard Jungman , Arthur Kosowsky , David N. Spergel

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

The measurement of the scale of the baryon acoustic oscillations (BAO) in the galaxy power spectrum as a function of redshift is a promising method to constrain the equation-of-state parameter of the dark energy w. To measure the scale of…

Astrophysics · Physics 2009-06-23 Christian Wagner , Volker Müller , Matthias Steinmetz

The most general homogeneous and isotropic statistical ensemble of linear scalar perturbations which are regular at early times, in a universe with only photons, baryons, neutrinos, and a cold dark matter (CDM) component, is described by a…

Astrophysics · Physics 2009-10-31 Martin Bucher , Kavilan Moodley , Neil Turok

We consider the simplest anisotropic generalization, as a correction, to the standard $\Lambda$CDM model, by replacing the spatially flat Robertson-Walker metric by the Bianchi type-I metric, which brings in a new term $\Omega_{\sigma…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-25 Ozgur Akarsu , Suresh Kumar , Shivani Sharma , Luigi Tedesco

If the hemispherical power asymmetry observed in the cosmic microwave background (CMB) on large angular scales is attributable to a superhorizon curvaton fluctuation, then the simplest model predicts that the primordial density fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Adrienne L. Erickcek , Christopher M. Hirata , Marc Kamionkowski

We compute the constraints on a ``standard'' 10 parameter cold dark matter (CDM) model from the most recent CMB and data and other observations, exploring 30 million discrete models and two continuous parameters. Our parameters are the…

Astrophysics · Physics 2009-09-25 Max Tegmark , Matias Zaldarriaga

We use joint likelihood analyses of combinations of fifteen cosmic microwave background (CMB) anisotropy data sets from the DMR, UCSB South Pole 1994, Python I--III, ARGO, MAX 4 and 5, White Dish, OVRO, and SuZIE experiments to constrain…

Comparison of theobservedanisotropy with that predicted iadiabaticDM models suggest that much of thserved signal may be due to long wavelenh gravitational waves. In inflationary models this requires the generation of tensor fluctuations to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Lawrence M. Krauss

The Cosmological Principle, that the Universe is homogeneous and isotropic on sufficiently large scales, underpins the standard model of cosmology. However, a recent analysis of 1.36 million infrared-selected quasars has identified a…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-08 Lawrence Dam , Geraint F. Lewis , Brendon J. Brewer

A new method is proposed to measure the Hubble constant H0 through the mean transmitted flux observed from high redshift quasars. A semi-analytical model for the cosmological-independent volume density distribution function is adopted which…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 V. C. Busti , R. N. Guimarães , J. A. S. Lima

The large-angular-scale anisotropy of the cosmic microwave background radiation in multidimensional cosmological models (Kaluza-Klein models) is studied. Limits on parameters of the models imposed by the experimental data are obtained. It…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Y. Kubyshin , J. Martin