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  • Open Access

Defect States in Compressible Active Polar Fluids with Renewal

Ludovic Dumoulin1,2, Carles Blanch-Mercader3,*, and Karsten Kruse1,2,†

  • *Contact author: carles.blanch-mercader@curie.fr
  • †Contact author: karsten.kruse@unige.ch
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PRX Life 4, 043009 – Published 3 November, 2026

DOI: https://doi.org/10.1103/bnx5-sryc

Abstract

Biological active matter like the cytoskeleton or tissues is characterized by its ability to transform chemical energy into mechanical stress. In addition, it often exhibits orientational order, which is essential for many cellular and morphogenetic processes. Experimental evidence suggests that defects in the orientational order field play an important role in organizing active stress. However, defects tend to annihilate unless the material is in a chaotic state or hydrodynamic interactions are suppressed. Using a hydrodynamic description of compressible active polar fluids, we show that renewal readily leads to a stabilization of defects. Depending on the renewal rate, topological defects arrange in a multitude of different phases, including lattices, active foams, and vortex glasses. Our work suggests that renewal plays a crucial role for organizing biological active matter.

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PRX Life 4, 043009– Published 3 November, 2026
  • Received 9 June 2025
  • Accepted 14 September 2026
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