Active fluids

The fluid mechanics of active materials, built around the idea of living systems as condensed matter made of free-energy-consuming particles, gives insight into biology and opens new directions in physics. Sriram Ramaswamy discusses the history and future of the field.

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The author thanks A. Maitra and M. Rao for stimulating conversations, and the SERB India and the Tata Education and Development Trust for support.

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Correspondence to Sriram Ramaswamy.

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The author declares no competing interests.

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Gareth Alexander (complex order):

Denis Bartolo (rolling colloid flocks):

Zvonimir Dogic (microtubule-motor active nematics):

Luca Giomi (theory of active defect hydrodynamics):

Ramin Golestanian (theory of self-phoretic motility):

Daphne Klotsa (active fluids with inertia):

Ananyo Maitra (ordered active fluids):

Ayusman Sen (swimming catalytic colloids):

Suraj Shankar (topology and active hydrodynamics):

Shuang Zhou (living liquid crystals):

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Ramaswamy, S. Active fluids. Nat Rev Phys 1, 640–642 (2019).

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