English
Related papers

Related papers: Another coincidence problem for $\Lambda$CDM?

200 papers

We obtain the reduced CMB data $\{l_A, R, z_*\}$ from WMAP9, WMAP9+BICEP2, Planck+WP and Planck+WP+BICEP2 for the $\Lambda$CDM and $w$CDM models with or without spatial curvature. We then use these reduced CMB data in combination with…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-06 Rong-Gen Cai , Zong-Kuan Guo , Bo Tang

We revisit the alignments of the largest structures observed in the cosmic microwave background (CMB) using the seven and nine-year WMAP and first-year Planck data releases. The observed alignments -- the quadrupole with the octopole and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

Under the assumption that the concordance Lambda-cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…

Astrophysics · Physics 2009-11-10 Louise M. Griffiths , Charles H. Lineweaver

We impose constraints on the topology of the Universe determined from a search for matched circles in the cosmic microwave background (CMB) temperature anisotropy patterns of the 7-year WMAP data. We pay special attention to the sensitivity…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-19 P. Bielewicz , A. J. Banday , K. M. Gorski

We present the first joint analysis of catalogs of radio galaxies and quasars to determine if their sky distribution is consistent with the standard $\Lambda$CDM model of cosmology. This model is based on the cosmological principle, which…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-29 Nathan Secrest , Sebastian von Hausegger , Mohamed Rameez , Roya Mohayaee , Subir Sarkar

We describe our methodology for comparing the WMAP measurements of the cosmic microwave background (CMB) and other complementary data sets to theoretical models. The unprecedented quality of the WMAP data, and the tight constraints on…

The largest uncollapsed inhomogeneity in the observable Universe is statistically represented in the quadrupole signal of the cosmic microwave background (CMB) sky maps as observed by the Wilkinson Microwave Anisotropy Probe (WMAP). The…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-09 Boudewijn F. Roukema

There is a deep cosmological mystery: although dependent on very different underlying physics, the timescales of structure formation, of galaxy cooling (both radiatively and against the CMB), and of vacuum domination do not differ by many…

High Energy Physics - Theory · Physics 2009-09-24 Raphael Bousso , Lawrence J. Hall , Yasunori Nomura

VAMP (variable-mass particles) scenarios, in which the mass of the cold dark matter particles is a function of the scalar field responsible for the present acceleration of the Universe, have been proposed as a solution to the cosmic…

Astrophysics · Physics 2009-11-10 Urbano Franca , Rogerio Rosenfeld

In the near future, observations of the cosmic microwave background (CMB) anisotropies will provide accurate determinations of many fundamental cosmological parameters. In this paper, we analyse degeneracies among cosmological parameters to…

Astrophysics · Physics 2009-10-30 G. Efstathiou , J. R. Bond

The standard model of cosmology, {\Lambda}CDM, is the simplest model that matches the current observations, but it relies on two hypothetical components, to wit, dark matter and dark energy. Future galaxy surveys and cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-13 Cyrille Doux , Mariana Penna-Lima , Sandro D. P. Vitenti , Julien Tréguer , Eric Aubourg , Ken Ganga

I describe briefly the Cosmic Microwave Background (hereafter CMB) physics which explains why high accuracy observations of its spatial structure are a unique observational tool both for the determination of the global cosmological…

Astrophysics · Physics 2007-05-23 Francois R. Bouchet

Decaying dark matter (DDM) is a candidate which can solve the discrepancies between predictions of the concordance $\Lambda$CDM model and observations at small scales such as the number counts of companion galaxies of the Milky Way and the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-17 Shohei Aoyama , Toyokazu Sekiguchi , Kiyotomo Ichiki , Naoshi Sugiyama

Recent improvements in astronomical observations lead to the conclusion that the Hubble constant lies between 60 and 80 Mpc km$^{-1}$ sec$^{-1}$ and the age of the universe between 11 and 14 Gigayears. Taken together with recent…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Pierre Noyes

(Abridged) The WMAP 5-year data strongly limit deviations from the minimal LCDM model. We constrain the physics of inflation via Gaussianity, adiabaticity, the power spectrum shape, gravitational waves, and spatial curvature. We also…

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 present a joint cosmological analysis combining data from the Planck satellite, the Atacama Cosmology Telescope, and the South Pole Telescope. We construct a unified likelihood that reproduces the measured temperature and polarisation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-24 M. Tristram , M. Douspis , A. Gorce , S. Henrot-Versillé , L. T. Hergt , S. Ilic , L. McBride , M. Muñoz-Echeverría , E. Pointecouteau , L. Salvati

We suggest that the solution to the cosmological vacuum energy puzzle does not require any new field beyond the standard model, but rather can be explained as a result of the interaction of the infrared sector of the effective theory of…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 Federico R. Urban , Ariel R. Zhitnitsky

Recent measurements of the cosmic microwave background radiation (CMB), particularly when combined with other datasets, have revolutionised our knowledge of the values of the basic cosmological parameters. Here we summarize the state of…

Astrophysics · Physics 2007-05-23 Ariel G. Sanchez , Carlton M. Baugh

The matching of our epoch of existence with the approximate equality of dark energy and dark matter energy densities is an apparent further fine-tuning, beyond the already troubling 120 orders of magnitude that separate dark energy from the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-17 Navin Sivanandam
‹ Prev 1 3 4 5 6 7 10 Next ›