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arXiv · hep-th/0307029

Effects of space-time noncommutativity on the angular power spectrum of the CMB

Masafumi Fukuma·Yuji Kono·Akitsugu Miwa
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Abstract

We investigate an inflationary model of the universe based on the assumption that space-time is noncommutative in the very early universe. We analyze the effects of space-time noncommutativity on the quantum fluctuations of an inflaton field and investigate their contributions to the cosmic microwave background (CMB). We show that the angular power spectrum l(l+1)C_l generically has a sharp damping for lower l if we assume that the last scattering surface is traced back to fuzzy spheres at the times when large-scale modes cross the Hubble horizon.

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Masafumi Fukuma, Yuji Kono, Akitsugu Miwa. 2004-01-20. Effects of space-time noncommutativity on the angular power spectrum of the CMB. https://doi.org/10.1016/j.nuclphysb.2004.01.020

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