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arXiv · 1710.06589

Anomalous Behaviour of Mutual Information in Finite Flocks

Lionel Barnett·Joshua Brown·Terry Bossomaier
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Abstract

The existing consensus is that flocks are poised at criticality, entailing long correlation lengths and a maximal value of Shannon mutual information in the large-system limit. We show, by contrast, that for finite flocks in the long observation time limit, mutual information may not only fail to peak at criticality---as observed for other critical systems---but also diverge as noise tends to zero. This result carries implications for other finite-size, out-of-equilibrium systems, where observation times may vary widely compared to time scales of internal system dynamics; thus it may not be assumed that mutual information locates the phase transition.

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Lionel Barnett, Joshua Brown, Terry Bossomaier. 2017-10-18. Anomalous Behaviour of Mutual Information in Finite Flocks. https://doi.org/10.1209/0295-5075%2F120%2F38005

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