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arXiv · 1308.2767

Building non commutative spacetimes at the Planck length for Friedmann flat cosmologies

Luca Tomassini·Stefano Viaggiu
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Abstract

We propose physically motivated spacetime uncertainty relations (STUR) for flat Friedmann-Lemaître cosmologies. We show that the physical features of these STUR crucially depend on whether a particle horizon is present or not. In particular, when this is the case we deduce the existence of a maximal value for the Hubble rate (or equivalently for the matter density), thus providing an indication that quantum effects may rule out a pointlike big bang singularity. Finally, we costruct a concrete realisation of the corresponding quantum Friedmann spacetime in terms of operators on a Hilbert space.

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Luca Tomassini, Stefano Viaggiu. 2014-08-29. Building non commutative spacetimes at the Planck length for Friedmann flat cosmologies. https://doi.org/10.1088/0264-9381%2F31%2F18%2F185001

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