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  • Letter
  • Open Access

Temperature of an active nematic

Jay Armas1,2,3,4,*, Akash Jain1,2,3,†, and Ruben Lier1,2,3,‡

  • *Contact author: j.armas@uva.nl
  • †Contact author: a.jain2@uva.nl
  • ‡Contact author: r.lier@uva.nl
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Phys. Rev. Research 8, L022011 – Published 13 April, 2026

DOI: https://doi.org/10.1103/9gww-wmyq

Abstract

We employ a hydrodynamic framework for active matter coupled to an environment to study the local temperature of an active nematic, assuming proximity to thermal equilibrium. We show that, due to the mechanosensitivity of fuel consumption, linearized temperature correlations in a homogeneous active nematic steady state remain unaffected by activity. However, we demonstrate that local shearing and twisting cause a confined active nematic undergoing a spontaneous flow transition to develop a distinctive inhomogeneous temperature profile, serving as a thermal signature of activity.

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Outline

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Phys. Rev. Research 8, L022011– Published 13 April, 2026
  • Received 29 August 2025
  • Accepted 20 February 2026
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