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Updated: Jul 6, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Coarse grained variables and deterministic chaos in an excitable system
Jhon F Martinez Avila1, Hugo L D de S Cavalcante, J R Rios Leite
1Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
Abstract:
Temporal coarse graining was applied to the dynamical variables of a semiconductor laser with optical feedback. The chaotic low frequency fluctuations obtained in numerical and experimental data are shown to have properties of a self-excitable deterministic system. External exciting noise is replaced by the ultrafast chaotic oscillations of the system. A low dimensional coarse-grained phase space is defined and time constants are introduced and measured for the exponential drop and recovery of the randomly excited equally shaped spikes.
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