English
Related papers

Related papers: Preferred axis in cosmology

200 papers

The cosmic microwave background (CMB) temperature maps from the Wilkinson Microwave Anisotropy Probe (WMAP) are of great importance for cosmology. In previous work we had developed a pipeline for map-making independently of the WMAP team.…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-23 Hao Liu , Shao-Lin Xiong , Ti-Pei Li

Einstein's theory of gravitation that governs the geometry of space-time, coupled with spectacular advance in cosmological observations, promises to deliver a `standard model' of cosmology in the near future. However, local geometry of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tarun Souradeep

The standard cosmological model predicts statistically isotropic cosmic microwave background (CMB) fluctuations characterized by the CMB temperature coefficients $a_{\ell m}$ being independent Gaussian random variables with zero mean and…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-17 Joann Jones , Craig J. Copi , Glenn D. Starkman , Yashar Akrami

We investigate the imprint of nonlinear matter condensations on the Cosmic Microwave Background (CMB) in an $\Omega=1$, Cold Dark Matter (CDM) model universe. Temperature anisotropies are obtained by numerically evolving matter…

Astrophysics · Physics 2016-08-30 Robin Tuluie , Pablo Laguna

Anomalies in the cosmic microwave background (CMB) refer to features that have been observed, mostly at large angular scales, and which show some tension with the statistical predictions of the standard $\Lambda$CDM model. In this work, we…

General Relativity and Quantum Cosmology · Physics 2021-05-28 Ivan Agullo , Dimitrios Kranas , V. Sreenath

We discuss the time dependence and future of the Cosmic Microwave Background (CMB) in the context of the standard cosmological model, in which we are now entering a state of endless accelerated expansion. The mean temperature will simply…

Astrophysics · Physics 2008-11-26 J. P. Zibin , A. Moss , D. Scott

Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The Causal Entropic Principle (Bousso, {\it et al}.) provides an…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-08 Brandon Bozek , Andreas Albrecht , Daniel Phillips

We present a Bayesian analysis of the Quaia sample of 1.3 million quasars as a test of the cosmological principle. This principle postulates that the universe is homogeneous and isotropic on sufficiently large scales, forming the basis of…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-16 Vasudev Mittal , Oliver T. Oayda , Geraint F. Lewis

We reconsider analysis of data on the cosmic microwave background on the largest angular scales. Temperature multipoles of any order factor naturally into a direct product of axial quantities and cosets. Striking coincidences exist among…

Astrophysics · Physics 2011-09-13 John P. Ralston , Pankaj Jain

The observed structures in the universe are thought to have arisen from gravitational instability acting on small fluctuations generated in the early universe. These spatial fluctuations are imprinted on the CMBR as angular anisotropies.…

Astrophysics · Physics 2008-11-26 Kandaswamy Subramanian

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

Modern cosmology rests on the working assumption that the Universe is isotropic and homogeneous at large scales. Here, we document a number of anomalous observations pointing to an anisotropic Universe in a direction consistent with the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-22 Eoin Ó Colgáin

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

Statistical Isotropy of the Cosmic Microwave Background (CMB) radiation has been studied and debated extensively in recent years. Under this assumption, the hot spots and cold spots of the CMB are expected to be uniformly distributed over a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-14 Md Ishaque Khan , Rajib Saha

The analysis of anisotropies in the cosmic microwave background (CMB) has become an extremely valuable tool for cosmology. We even have hopes that planned CMB anisotropy experiments may revolutionize cosmology. Together with determinations…

Astrophysics · Physics 2011-04-15 Ruth Durrer

We determine here peculiar motion of the Solar system, first time from the $m-z$ Hubble diagram of quasars. Observer's peculiar motion causes a systematic shift in the $m-z$ plane between sources lying along the velocity vector and those in…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-14 Ashok K. Singal

We present a pedagogical and phenomenological introduction to the study of cosmic microwave background (CMB) polarization to build intuition about the prospects and challenges facing its detection. Thomson scattering of temperature…

Astrophysics · Physics 2009-08-18 Wayne Hu , Martin White

The angular distribution of the Cosmic Microwave Background Radiation (CMBR) in sky shows a dipole asymmetry, ascribed to the observer's motion (peculiar velocity of the solar system!), relative to the local comoving coordinates. The…

General Physics · Physics 2019-09-11 Ashok K. Singal

We study the large-scale anisotropy of the Universe by measuring the dipole in the angular distribution of a flux-limited, all-sky sample of 1.36 million quasars observed by the Wide-field Infrared Survey Explorer (WISE). This sample is…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-01 Nathan Secrest , Sebastian von Hausegger , Mohamed Rameez , Roya Mohayaee , Subir Sarkar , Jacques Colin
‹ Prev 1 3 4 5 6 7 10 Next ›