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DOE OSTI · 22848285

A discrete classical space-time could require 6 extra-dimensions

Guillemant, Philippe·Medale, Marc·Abid, Cherifa
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Abstract

We consider a discrete space–time in which conservation laws are computed in such a way that the density of information is kept bounded. We use a 2D billiard as a toy model to compute the uncertainty propagation in ball positions after every shock and the corresponding loss of phase information. Our main result is the computation of a critical time step above which billiard calculations are no longer deterministic, meaning that a multiverse of distinct billiard histories begins to appear, caused by the lack of information. Then, we highlight unexpected properties of this critical time step and the subsequent exponential evolution of the number of histories with time, to observe that after certain duration all billiard states could become possible final states, independent of initial conditions. We conclude that if our space–time is really a discrete one, one would need to introduce extra-dimensions in order to provide supplementary constraints that specify which history should be played.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSCALCULATION METHODSCOMPUTERIZED SIMULATIONCONSERVATION LAWSDENSITYLIMITING VALUESMANY-DIMENSIONAL CALCULATIONSQUANTUM MECHANICSSPACE-TIME

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Guillemant, Philippe, Medale, Marc, Abid, Cherifa. 2018-01-15. A discrete classical space-time could require 6 extra-dimensions. https://doi.org/10.1016/j.aop.2017.11.023

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