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  • Open Access

Information Bound on Navigation Speed in Smart Active Matter

Kristian Stølevik Olsen1,*, Mitsusuke Tarama2, and Hartmut Löwen1

  • *Contact author: kristian.olsen@hhu.de
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Phys. Rev. Lett. 137, 157101 – Published 9 October, 2026

DOI: https://doi.org/10.1103/xs9l-1233

Abstract

Intelligent behavior in lifelike systems often arises from the ability to gather, process, and act on information. While active matter provides a framework for studying lifelike dynamics, it typically omits internal information processing and decision making. Here we introduce an adaptive active particle model that uses minimal information processing capabilities in order to navigate toward a distant target. By combining renewal-based intermittent motion with the Cramér-Rao inequality, we derive a bound on the navigation speed valid for a wide range of information processing strategies. The framework captures hallmark features of cognitive systems, including optimal sensing durations and a trade-off that balances noise and reliability. Allowing stored information to degrade before action reveals that, although deterioration slows navigation, the trade-off remains governed primarily by external orientational noise and is remarkably insensitive to memory decay.

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Outline

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Phys. Rev. Lett. 137, 157101– Published 9 October, 2026
  • Received 3 March 2026
  • Accepted 15 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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