English

Integral Hilbert spaces and the dynamics of loop quantum cosmos

General Relativity and Quantum Cosmology 2026-08-03 v1 Numerical Analysis Computational Physics

Abstract

Polymer quantization program applied in Loop Quantum Gravity/Cosmology leads to nonseparable Hilbert spaces. Commonly, one sidesteps this problem by singling out and working with a separable superselection sector. This is however often no longer accessible in more involved models beyond isotropic ones. In an alternative approach one builds a separable Hilbert space as an integral over all available sectors. Here we test the dynamics following from the latter on the example of a flat isotropic Universe admitting negative cosmological constant and a massless scalar field. There, numerical evolution of (initially) semiclassical states shows that there is no relevant difference in their long term semiclassicality properties in comparison to those in a single sector approach. Further, the older (problem-specific) numerical methods are compared against an application of more common and more efficient standard tools (eigen library).

Keywords

Cite

@article{arxiv.2608.02798,
  title  = {Integral Hilbert spaces and the dynamics of loop quantum cosmos},
  author = {Janek Kozicki and Tomasz Pawłowski},
  journal= {arXiv preprint arXiv:2608.02798},
  year   = {2026}
}

Comments

24 pages, 12 figures, 2 listings, submitted to Physical Review D