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Poisson-to-Wigner crossover transition in the nearest-neighbor spacing statistics of random points on fractals

Jamal Sakhr·John M. Nieminen
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Abstract

We show that the nearest-neighbor spacing distribution for a model that consists of random points uniformly distributed on a self-similar fractal is the Brody distribution of random matrix theory. In the usual context of Hamiltonian systems, the Brody parameter does not have a definite physical meaning, but in the model considered here, the Brody parameter is actually the fractal dimension. Exploiting this result, we introduce a new model for a crossover transition between Poisson and Wigner statistics: random points on a continuous family of self-similar curves with fractal dimension between 1 and 2. The implications to quantum chaos are discussed, and a connection to conservative classical chaos is introduced.

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Jamal Sakhr, John M. Nieminen. 2005-11-21. Poisson-to-Wigner crossover transition in the nearest-neighbor spacing statistics of random points on fractals. https://doi.org/10.1103/physreve.72.045204

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