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arXiv · 2507.14644

Intrinsic pressure as a convenient mechanical framework for dry active matter

Zihao Sun·Longfei Li·Chuyun Wang·Jing Wang·Huaicheng Chen·Gao Wang·Liyu Liu·Fangfu Ye·Mingcheng Yang
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Abstract

The identification of local pressure in active matter systems remains a subject of considerable debate. Through theoretical calculations and extensive simulations of various active systems, we demonstrate that intrinsic pressure (defined in the same way as in passive systems) is an ideal candidate for local pressure of dry active matter, while the self-propelling forces on the active particles are considered as effective external forces originating from the environment. Such a framework is universal and especially convenient for analyzing mechanics of dry active systems, and it recovers the conventional scenario of mechanical equilibrium well-known in passive systems. Thus, our work is of fundamental importance to further explore mechanics and thermodynamics of complex active systems.

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Zihao Sun, Longfei Li, Chuyun Wang, Jing Wang, Huaicheng Chen, Gao Wang, Liyu Liu, Fangfu Ye, Mingcheng Yang. 2025-07-19. Intrinsic pressure as a convenient mechanical framework for dry active matter. https://arxiv.org/abs/2507.14644

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