Path integral renormalization in loop quantum cosmology
نویسندگان
چکیده
A coarse graining technique akin to block spin transformations that groups together fiducial cells in a homogeneous and isotropic universe has been recently developed the context of loop quantum cosmology. The key technical ingredient was an SU(1, 1) group Lie algebra structure physical observables as well use Perelomov coherent states for 1). It shown operation is completely captured by changing representations. Based on this result, it subsequently one can extract explicit renormalisation flow cosmology Hamiltonian operator simple model with dust-clock. In paper, we continue line investigation derive state path integral formulation theory expression renormalisation-scale dependent classical entering grained description at scale. We find corrections non-renormalised are qualitatively similar those previously investigated via canonical quantisation. particular, they again most sensitive small numbers, showing large number (spin) so called "effective equations" does not reproduce physics many numbers (spins). Our results have direct impact quantisation gravity, usually taken limit should be expected capture (without renormalisation, mostly done) spins assumed present physically reasonable states.
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ژورنال
عنوان ژورنال: Physical review
سال: 2021
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physrevd.103.126021