The preinflationary dynamics of loop quantum cosmology: confronting quantum gravity with observations
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 preinflationary dynamics. The framework enables us to isolate and resolve the true transPlanckian 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 nonGaussianities—which could extend the reach of cosmological observations to the deep Planck regime of the early universe.
Communicated by P Singh
 Publication:

Classical and Quantum Gravity
 Pub Date:
 April 2013
 DOI:
 10.1088/02649381/30/8/085014
 arXiv:
 arXiv:1302.0254
 Bibcode:
 2013CQGra..30h5014A
 Keywords:

 General Relativity and Quantum Cosmology;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 64 pages, 15 figures. Published version