This possibly has a chance of being ignored, but Ashtekar is a name that should be familiar to someone here (I hope):
Quote:
Loop quantum cosmology ...
Abhay Ashtekar and Edward Wilson-Ewing
Loop quantum cosmology (LQC) [4, 5] is constructed by applying methods of LQG to mini-superspaces obtained by a symmetry reduction of general relativity. In the homogeneous, isotropic cosmological models with a massless scalar field, quantum geometry effects of LQG have been shown to create a new repulsive force in the Planck regime. The force is so strong that the big bang is replaced by a specific type of quantum bounce.
Detailed and viable quantum theories were constructed in the homogeneous, isotropic case using the so-called “ ” scheme. A key open question has been whether or not the qualitative features of their Planck scale physics will persist in more realistic situations in which these strong symmetry assumptions do not hold exactly. A first step in this direction is to retain homogeneity and extend the “improved dynamics” of [10] to anisotropic situations.
In the isotropic case, there is only one non-trivial curvature invariant, the (space-time) scalar curvature (or, equivalently, matter density). In anisotropic situations Weyl curvature is non-zero and it too diverges at the big bang. Therefore, now one can enter the Planck regime in several inequivalent ways which suggests that the Planck scale physics would now be much richer.
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