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arXiv · 1302.0254

The pre-inflationary dynamics of loop quantum cosmology: Confronting quantum gravity with observations

Ivan Agullo·Abhay Ashtekar·William Nelson
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Abstract

Using techniques from loop quantum gravity, the standard theory of cosmological perturbations was recently generalized to encompass the Planck era. We now apply this framework to explore pre-inflationary dynamics. The framework enables us to isolate and resolve the true trans-Planckian difficulties, with interesting lessons both for theory and observations. Specifically, for a large class of initial conditions at the bounce, we are led to a self consistent extension of the inflationary paradigm over the 11 orders of magnitude in density and curvature, from the big bounce to the onset of slow roll. In addition, for a narrow window of initial conditions, there are departures from the standard paradigm, with novel effects ---such as a modification of the consistency relation between the ratio of the tensor to scalar power spectrum and the tensor spectral index, as well as a new source for non-Gaussianities--- which could extend the reach of cosmological observations to the deep Planck regime of the early universe.

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Ivan Agullo, Abhay Ashtekar, William Nelson. 2013-02-01. The pre-inflationary dynamics of loop quantum cosmology: Confronting quantum gravity with observations. https://doi.org/10.1088/0264-9381/30/8/085014

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