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arXiv · 1511.08743

Entropies for severely contracted configuration space

G. Cigdem Yalcin·Carlos Velarde·Alberto Robledo
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Abstract

We demonstrate that dual entropy expressions of the Tsallis type apply naturally to statistical-mechanical systems that experience an exceptional contraction of their configuration space. The entropic index $α>1$ describes the contraction process, while the dual index $α^{\prime }=2-α<1$ defines the contraction dimension at which extensivity is restored. We study this circumstance along the three routes to chaos in low-dimensional nonlinear maps where the attractors at the transitions, between regular and chaotic behavior, drive phase-space contraction for ensembles of trajectories. We illustrate this circumstance for properties of systems that find descriptions in terms of nonlinear maps. These are size-rank functions, urbanization and similar processes, and settings where frequency locking takes place.

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G. Cigdem Yalcin, Carlos Velarde, Alberto Robledo. 2015-11-27. Entropies for severely contracted configuration space. https://doi.org/10.1016/j.heliyon.2015.e00045

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