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arXiv · 1103.0299

CMB Fluctuations and String Compactification Scales

Yoshinobu Habara·Hikaru Kawai·Masao Ninomiya·Yasuhiro Sekino
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Abstract

We propose a mechanism for the generation of temperature fluctuations of cosmic microwave background. We consider a large number of fields, such as Kaluza-Klein modes and string excitations. Each field contributes to the gravitational potential by a small amount, but an observable level of temperature fluctuations is achieved by summing up the contribution of typically of order 10^{14} fields. Tensor fluctuations are hardly affected by these fields. Our mechanism is based on purely quantum effects, and is different from the "slow-roll" or "curvaton" scenario. Using the observed data, we find constraints on the parameters of this model, such as the size of the extra dimensions and the string scale. Our model predicts a particular pattern of non-gaussianity with a small magnitude.

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Yoshinobu Habara, Hikaru Kawai, Masao Ninomiya, Yasuhiro Sekino. 2011-12-12. CMB Fluctuations and String Compactification Scales. https://doi.org/10.1016/j.physletb.2011.12.018

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