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arXiv · 1506.04984

Is there a quantum gravity effect on the cosmic microwave background power spectrum?

Donato Bini·Giampiero Esposito
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Abstract

An assessment is made of recent attempts to evaluate how quantum gravity may affect the anisotropy spectrum of the cosmic microwave background. A perturbative scheme for the solution of the Wheeler-DeWitt equation has been found to allow for enhancement of power at large scales, whereas the alternative predicts a suppression of power at large scales. Both effects are corrections which, although conceptually interesting, turn out to be too small to be detected. Another scheme relies upon a Born-Oppenheimer analysis: by using a perturbative approach to the nonlinear ordinary differential equation obeyed by the two-point function for scalar fluctuations, a new family of power spectra have been obtained and studied by the authors.

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Donato Bini, Giampiero Esposito. 2015-06-16. Is there a quantum gravity effect on the cosmic microwave background power spectrum?. https://arxiv.org/abs/1506.04984

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