On exact statistics and classification of ergodic systems of integer dimension

Zachary Guralnik; Cengiz Pehlevan; Gerald Guralnik

doi:10.1063/1.4881890

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arXiv · 1311.7157

On exact statistics and classification of ergodic systems of integer dimension

Zachary Guralnik·Cengiz Pehlevan·Gerald Guralnik

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Abstract

We describe classes of ergodic dynamical systems for which some statistical properties are known exactly. These systems have integer dimension, are not globally dissipative, and are defined by a probability density and a two-form. This definition generalizes the construction of Hamiltonian systems by a Hamiltonian and a symplectic form. Some low dimensional examples are given, as well as a discretized field theory with a large number of degrees of freedom and a local nearest neighbor interaction. We also evaluate unequal-time correlations of these systems without direct numerical simulation, by Padé approximants of a short-time expansion. We briefly speculate on the possibility of constructing chaotic dynamical systems with non-integer dimension and exactly known statistics. In this case there is no probability density, suggesting an alternative construction in terms of a Hopf characteristic function and a two-form.

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Zachary Guralnik, Cengiz Pehlevan, Gerald Guralnik. 2014-05-21. On exact statistics and classification of ergodic systems of integer dimension. https://doi.org/10.1063/1.4881890

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