Imprints of a primordial preferred direction on the microwave background
Abstract
Rotational invariance is a wellestablished feature of lowenergy physics. Violations of this symmetry must be extremely small today, but could have been larger in earlier epochs. In this paper we examine the consequences of a small breaking of rotational invariance during the inflationary era when the primordial density fluctuations were generated. Assuming that a fixednorm vector picked out a preferreddirection during the inflationary era, we explore the imprint it would leave on the cosmic microwave background anisotropy, and provide explicit formulas for the expected amplitudes <a{sub lm}a{sub l{sup '}}{sub m{sup '}}*> of the sphericalharmonic coefficients. We suggest that it is natural to expect that the imprint on the primordial power spectrum of a preferred spatial direction is approximately scaleinvariant, and examine a simple model in which this is true.
 Authors:
 California Institute of Technology, Pasadena, California 91125 (United States)
 Publication Date:
 OSTI Identifier:
 21020344
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.083502; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; ANISOTROPY; COSMOLOGY; FLUCTUATIONS; RELICT RADIATION; ROTATIONAL INVARIANCE; SPHERICAL CONFIGURATION; SYMMETRY
Citation Formats
Ackerman, Lotty, Carroll, Sean M., and Wise, Mark B. Imprints of a primordial preferred direction on the microwave background. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.083502.
Ackerman, Lotty, Carroll, Sean M., & Wise, Mark B. Imprints of a primordial preferred direction on the microwave background. United States. doi:10.1103/PHYSREVD.75.083502.
Ackerman, Lotty, Carroll, Sean M., and Wise, Mark B. Sun .
"Imprints of a primordial preferred direction on the microwave background". United States.
doi:10.1103/PHYSREVD.75.083502.
@article{osti_21020344,
title = {Imprints of a primordial preferred direction on the microwave background},
author = {Ackerman, Lotty and Carroll, Sean M. and Wise, Mark B.},
abstractNote = {Rotational invariance is a wellestablished feature of lowenergy physics. Violations of this symmetry must be extremely small today, but could have been larger in earlier epochs. In this paper we examine the consequences of a small breaking of rotational invariance during the inflationary era when the primordial density fluctuations were generated. Assuming that a fixednorm vector picked out a preferreddirection during the inflationary era, we explore the imprint it would leave on the cosmic microwave background anisotropy, and provide explicit formulas for the expected amplitudes <a{sub lm}a{sub l{sup '}}{sub m{sup '}}*> of the sphericalharmonic coefficients. We suggest that it is natural to expect that the imprint on the primordial power spectrum of a preferred spatial direction is approximately scaleinvariant, and examine a simple model in which this is true.},
doi = {10.1103/PHYSREVD.75.083502},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}

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