skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Relic vector field and CMB large scale anomalies

Abstract

We study the most general effects of relic vector fields on the inflationary background and density perturbations. Such effects are observable if the number of inflationary e-folds is close to the minimum requirement to solve the horizon problem. We show that this can potentially explain two CMB large scale anomalies: the quadrupole-octopole alignment and the quadrupole power suppression. We discuss its effect on the parity anomaly. We also provide analytical template for more detailed data comparison.

Authors:
 [1];  [2]
  1. Department of Physics, The University of Texas at Dallas, Richardson, TX 75083 (United States)
  2. Centre for Theoretical Cosmology, DAMTP, University of Cambridge, Cambridge CB3 0WA (United Kingdom)
Publication Date:
OSTI Identifier:
22375825
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALIGNMENT; DENSITY; PARITY; POTENTIALS; VECTOR FIELDS

Citation Formats

Chen, Xingang, and Wang, Yi, E-mail: Xingang.Chen@utdallas.edu, E-mail: yw366@cam.ac.uk. Relic vector field and CMB large scale anomalies. United States: N. p., 2014. Web. doi:10.1088/1475-7516/2014/10/027.
Chen, Xingang, & Wang, Yi, E-mail: Xingang.Chen@utdallas.edu, E-mail: yw366@cam.ac.uk. Relic vector field and CMB large scale anomalies. United States. doi:10.1088/1475-7516/2014/10/027.
Chen, Xingang, and Wang, Yi, E-mail: Xingang.Chen@utdallas.edu, E-mail: yw366@cam.ac.uk. 2014. "Relic vector field and CMB large scale anomalies". United States. doi:10.1088/1475-7516/2014/10/027.
@article{osti_22375825,
title = {Relic vector field and CMB large scale anomalies},
author = {Chen, Xingang and Wang, Yi, E-mail: Xingang.Chen@utdallas.edu, E-mail: yw366@cam.ac.uk},
abstractNote = {We study the most general effects of relic vector fields on the inflationary background and density perturbations. Such effects are observable if the number of inflationary e-folds is close to the minimum requirement to solve the horizon problem. We show that this can potentially explain two CMB large scale anomalies: the quadrupole-octopole alignment and the quadrupole power suppression. We discuss its effect on the parity anomaly. We also provide analytical template for more detailed data comparison.},
doi = {10.1088/1475-7516/2014/10/027},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2014,
place = {United States},
year = 2014,
month =
}
  • Solar filaments are commonly thought to be supported in magnetic dips, in particular, in those of magnetic flux ropes (FRs). In this Letter, based on the observed photospheric vector magnetogram, we implement a nonlinear force-free field (NLFFF) extrapolation of a coronal magnetic FR that supports a large-scale intermediate filament between an active region and a weak polarity region. This result is a first, in the sense that current NLFFF extrapolations including the presence of FRs are limited to relatively small-scale filaments that are close to sunspots and along main polarity inversion lines (PILs) with strong transverse field and magnetic shear,more » and the existence of an FR is usually predictable. In contrast, the present filament lies along the weak-field region (photospheric field strength ≲ 100 G), where the PIL is very fragmented due to small parasitic polarities on both sides of the PIL and the transverse field has a low signal-to-noise ratio. Thus, extrapolating a large-scale FR in such a case represents a far more difficult challenge. We demonstrate that our CESE-MHD-NLFFF code is sufficient for the challenge. The numerically reproduced magnetic dips of the extrapolated FR match observations of the filament and its barbs very well, which strongly supports the FR-dip model for filaments. The filament is stably sustained because the FR is weakly twisted and strongly confined by the overlying closed arcades.« less
  • Recently, the relation between Hawking radiation and gravitational anomalies has been used to estimate the flux of Hawking radiation for a large class of black objects. In this paper, we extend the formalism, originally proposed by Robinson and Wilczek, to the Hawking radiation of vector particles (photons). It is explicitly shown, with the Hamiltonian formalism, that the theory of an electromagnetic field on d-dimensional spherical black holes reduces to one of an infinite number of massive complex scalar fields on 2-dimensional spacetime, for which the usual anomaly-cancellation method is available. It is found that the total energy emitted from themore » horizon for the electromagnetic field is just (d-2) times that for a scalar field. The results support the picture that Hawking radiation can be regarded as an anomaly eliminator on horizons. Possible extensions and applications of the analysis are discussed.« less
  • This study examines the broad aspects of large-scale interannual and long-term variability in the monthly mean outgoing longwave radiation (OLR) data over the global tropics. The data is from NOAA's polar-orbiting satellites. Rotated principal component analysis (RPCA) has been performed on monthly OLR anomalies over the global tropics (30[degrees]-30[degrees]S) on a 10[degrees] longitude by 5[degrees] latitude grid for the period from June 1974 through March 1989, excluding calendar year 1978. The leading rotated principal components have been tested for robustness and reproducibility. The spatial-loading pattern and the time series for the first principal component ([open quotes]canonical ENSO[close quotes] mode) representmore » the major large-scale features in the tropics during the typical phase of the major warm and cold events in the tropical Pacific. The characteristics of the dramatic 1982/83 warm event that were different from the canonical ENSO mode completely dominate the second RPC (termed the 1982/83 mode). The third and fourth leading RPCs appear to describe the changes in the satellite-observing system. Of the six leading modes considered, the [open quotes]nonphysical[close quotes] modes (3 and 4) accounted for more than 40% of the explained variance over North Africa and northeastern South America. The physical modes (1, 2, 5, and 6) explained more than 70% of the variance in the central equatorial and eastern Pacific Ocean. While the eigenmodes that result from unrotated principal component analysis are sensitive to small changes in analysis domain and period, those of the rotated analysis are fairly stable. However, the [open quotes] 1982/83 mode,[close quotes] is unique to the analysis period (1974-89). The results of the sensitivity analysis do not provide strong support of the claim by other authors that the decade of the 1980s, as compared to the 1970s, experienced enhanced levels of convective activity in the tropical Pacific and Indian oceans.« less
  • We study the alignments of the low multipoles of CMB anisotropies with specific directions in the sky (i.e. the dipole, the north Ecliptic pole, the north Galactic pole and the north Super Galactic pole). Performing 10{sup 5} random extractions we have found that: 1) separately quadrupole and octupole are mildly orthogonal to the dipole but when they are considered together, in analogy to Copi2006, we find an unlikely orthogonality at the level of 0.8% C.L.; 2) the multipole vectors associated to l = 4 are unlikely aligned with the dipole at 99.1% C.L.; 3) the multipole vectors associated to lmore » = 5 are mildly orthogonal to the dipole but when we consider only maps that show exactly the same correlation among the multipoles as in the observed WMAP 5yr ILC, these multipole vectors are unlikely orthogonal to the dipole at 99.7% C.L.« less