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Signatures of Planck-scale interactions in the cosmic microwave background?

Friedemann Queisser·Michael Uhlmann·Ralf Schützhold
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Abstract

Based on a rather general low-energy effective action (interacting quantum fields in classical curved space-times), we calculate potential signatures of new physics (such as quantum gravity) at ultra-high energies (presumably the Planck scale) in the anisotropies of the cosmic microwave background. These Planck-scale interactions create non-Gaussian contributions, where special emphasis is laid on the three-point function as the most promising observable, which also allows the discrimination between models violating and those obeying Lorentz invariance. PACS: 98.80.Cq, 04.62.+v, 98.70.Vc, 98.80.Qc.

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Friedemann Queisser, Michael Uhlmann, Ralf Schützhold. 2006-01-25. Signatures of Planck-scale interactions in the cosmic microwave background?. https://doi.org/10.1088/0264-9381%2F24%2F6%2F001

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