English

Discrete fuzzy de Sitter cosmology

High Energy Physics - Theory 2019-07-31 v2 General Relativity and Quantum Cosmology

Abstract

We analyze the spectrum of time observable in noncommutative cosmological model introduced in [5], defined by (ρ,s=12)(\rho, s=\frac 12)\, representation of the de Sitter group. We find that time has peculiar property: it is not self-adjoint, but appropriate restrictions to the space of physical states give self-adjoint extensions. Extensions have discrete spectrum with logarithmic distribution of eigenvalues, tnlogn\,t_n \sim \ell\, \log\, n+const, where \ell characterizes noncommutativity and the usual assumption is =Planck\,\ell=\ell_{Planck}. When calculated on physical states, radius of the universe is bounded below by 34(14+ρ2)\, \ell\, \sqrt{\frac 34\, \left( \frac 14 +\rho^2\right)}\, , which resolves the big bang singularity. An immediate consequence of the model is a specific breaking of the original symmetry at the Planck scale.

Keywords

Cite

@article{arxiv.1903.08378,
  title  = {Discrete fuzzy de Sitter cosmology},
  author = {Maja Buric and Dusko Latas},
  journal= {arXiv preprint arXiv:1903.08378},
  year   = {2019}
}

Comments

22 pages, 1 figure

R2 v1 2026-06-23T08:13:40.315Z