Discrete fuzzy de Sitter cosmology

Abstract

We analyze the spectrum of time observable in noncommutative cosmological model introduced in [5], defined by (ρ, s = 1 2 ) 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, t n ∼ log n+const, where characterizes noncommutativity and the usual assumption is = P lanck . When calculated on physical states, radius of the universe is bounded below by 3 4 1 4 + ρ 2 , which resolves the big bang singularity. An immediate consequence of the model is a specific breaking of the original symmetry at the Planck scale. * majab@ipb.ac.rs, latas@ipb.ac.rs 1 arXiv:1903.08378v2 [hep-th]

Asymptotic freedom for $$\lambda \phi ^4_{\star }$$ QFT in Snyder–de Sitter space

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Ampelographic and Genetic Characterization of Montenegrin Grapevine Varieties

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Noncommutativity and the weak cosmic censorship

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