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Related papers: The axis of evil

200 papers

We revisit the anisotropic universe model previously developed by Ackerman, Carroll and Wise (ACW), and generalize both the theoretical and computational framework to include polarization and various forms of systematic effects. We apply…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Nicolaas E. Groeneboom , Lotty Ackerman , Ingunn Kathrine Wehus , Hans Kristian Eriksen

The cosmic dipole anomaly, currently detected at a significance exceeding 5$\sigma$ in several independent survey poses a significant challenge to the standard model of cosmology. The Ellis & Baldwin formula provides a theoretical link…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Albert Bonnefous

The lack of power of large--angle CMB anisotropies is known to increase its statistical significance at higher Galactic latitudes, where a string--inspired pre--inflationary scale $\Delta$ can also be detected. Considering the Planck 2015…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-13 A. Gruppuso , N. Kitazawa , M. Lattanzi , N. Mandolesi , P. Natoli , A. Sagnotti

The excess of cosmic-ray positrons in the energy range from 10 GeV to few hundred GeV reported by PAMELA and AMS experiments is not consistent with a pure secondary origin and requires the introduction of a source term. The presence of…

Instrumentation and Methods for Astrophysics · Physics 2015-10-07 J. Berdugo , J. Casaus , C. Mana , M. A. Velasco

Both WMAP and Planck data show a significant odd-multipole preference in the large scales of the cosmic microwave background (CMB) temperature anisotropies. If this pattern originates from cosmological effects, then it can be considered a…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-18 Cheng Cheng , Wen Zhao , Qing-Guo Huang , Larissa Santos

This research demonstrates that parity violation in general relativity can simultaneously explain the observed loss in power and alignment at a preferred axis ('Axis of Evil')in the low multipole moments of the WMAP data. This observational…

High Energy Physics - Theory · Physics 2008-11-26 Stephon H. S. Alexander

Modern cosmology rests on the cosmological principle, that on large enough scales the Universe is both homogeneous and isotropic. A corollary is that galaxies' spin vectors should be isotropically distributed on the sky. This has been…

Astrophysics of Galaxies · Physics 2025-03-03 Dhruva Patel , Harry Desmond

The direction and magnitude of the dipole anisotropy of ultra-high-energy cosmic rays with energies above 8 EeV observed by the Pierre Auger Observatory indicate their extragalactic origin. The observed dipole on Earth does not necessarily…

High Energy Astrophysical Phenomena · Physics 2024-02-13 Alena Bakalová , Jakub Vícha , Petr Trávníček

We study hemispherical power asymmetry (Eriksen et. al. 2004, Hansen et. al. 2004, Hansen et. al. 2009) in the WMAP 9-year data. We analyse the combined V- and W-band sky maps, after application of the KQ85 mask, and find that the asymmetry…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-29 M. Axelsson , Y. Fantaye , F. K. Hansen , A. J. Banday , H. K. Eriksen , K. M. Gorski

Parity violation in the cosmic microwave background (CMB) radiation has been confirmed by recent Planck observation. In this paper, we extend our previous work [P. Naselsky et al. Astrophys. J. {\bf 749}, 31 (2012)] on the directional…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-16 Wen Zhao

We discuss the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.64 10^{-2}$, we find an average large scale…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-18 Paolo Cea

We repeat and extend the analysis of Eriksen et al 2004 and Hansen et al 2004 testing the isotropy of the Cosmic Microwave Background (CMB) fluctuations. We find that the hemispherical power asymmetry previously reported for the largest…

Astrophysics · Physics 2014-11-18 F. K. Hansen , A. J. Banday , K. M. Gorski , H. K. Eriksen , P. B. Lilje

Recent released Planck data and other astronomical observations show that the universe may be anisotropic on large scales. This hints a cosmological privileged axis in our anisotropic expanding universe. This paper proceeds a modified…

General Relativity and Quantum Cosmology · Physics 2017-11-29 Amin Salehi , Mohammad Reza Setare

Anomalies of the cosmic microwave background (CMB) maps have been widely acquainted nowadays from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to the Planck satellite. One of the anomalies is a multipole alignment from $l=2$ to…

High Energy Astrophysical Phenomena · Physics 2014-06-30 Lixiong Gan , Yuan-Chuan Zou , Zi-Gao Dai

We study several anisotropic inflationary models and their implications for the observed violation of statistical isotropy in the CMBR data. In two of these models the anisotropy decays very quickly during the inflationary phase of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Pranati K. Rath , Tanmay Mudholkar , Pankaj Jain , Pavan K. Aluri , Sukanta Panda

In the standard diffusive picture for transport of cosmic rays (CRs), a gradient in the CR density induces a typically small, dipolar anisotropy in their arrival directions. This has been widely advertised as a tool for finding nearby…

High Energy Astrophysical Phenomena · Physics 2015-01-15 Philipp Mertsch , Stefan Funk

We search a sample of photometric luminous red galaxies (LRGs) measured by the Sloan Digital Sky Survey (SDSS) for a quadrupolar anisotropy in the primordial power spectrum, in which P(\vec{k}) is an isotropic power spectrum P(k) multiplied…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 Anthony R. Pullen , Christopher M. Hirata

Auger Collaboration has reported a large-scale anisotropy in the arrival directions of cosmic rays above 8 EeV. The dipole direction, at 125$^\circ$ from the Galactic center, is taken as an indication of an extragalactic origin of these…

High Energy Astrophysical Phenomena · Physics 2018-08-02 Andrei Gruzinov

Polarization results from the Cosmic Anisotropy Polarization MAPper (CAPMAP) experiment are reported. These are based upon 433 hours, after cuts, observing a 2 square degree patch around the North Celestial Pole (NCP) with four 90 GHz…

We introduce new symmetry-based methods to test for isotropy in cosmic microwave background radiation. Each angular multipole is factored into unique products of power eigenvectors, related multipoles and singular values that provide 2 new…

Astrophysics · Physics 2008-11-26 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston