Testing loop quantum cosmology

Publication date: Available online 16 March 2017 Source:Comptes Rendus Physique Author(s): Edward Wilson-Ewing Loop quantum cosmology predicts that quantum gravity effects resolve the big-bang singularity and replace it by a cosmic bounce. Furthermore, loop quantum cosmology can also modify the form of primordial cosmological perturbations, for example by reducing power at large scales in inflationary models or by suppressing the tensor-to-scalar ratio in the matter bounce scenario; these two effects are potential observational tests for loop quantum cosmology. In this article, I review these predictions and others, and also briefly discuss three open problems in loop quantum cosmology: its relation to loop quantum gravity, the trans-Planckian problem, and a possible transition from a Lorentzian to a Euclidean space–time around the bounce point.

Source: Comptes Rendus Physique - March 16, 2017 Category: Physics Source Type: research