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Translational Invariance and the Anisotropy of the Cosmic Microwave Background

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 نشر من قبل Sean Carroll
 تاريخ النشر 2010
  مجال البحث فيزياء
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Primordial quantum fluctuations produced by inflation are conventionally assumed to be statistically homogeneous, a consequence of translational invariance. In this paper we quantify the potentially observable effects of a small violation of translational invariance during inflation, as characterized by the presence of a preferred point, line, or plane. We explore the imprint such a violation would leave on the cosmic microwave background anisotropy, and provide explicit formulas for the expected amplitudes $<a_{lm}a_{lm}^*>$ of the spherical-harmonic coefficients.



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