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A Simplest Swimmer at Low Reynolds Number: Three Linked Spheres

Ali Najafi·Ramin Golestanian
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Abstract

We propose a very simple one-dimensional swimmer consisting of three spheres that are linked by rigid rods whose lengths can change between two values. With a periodic motion in a non-reciprocal fashion, which breaks the time-reversal symmetry as well as the translational symmetry, we show that the model device can swim at low Reynolds number. This model system could be used in constructing molecular-size machines.

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Ali Najafi, Ramin Golestanian. 2004-02-03. A Simplest Swimmer at Low Reynolds Number: Three Linked Spheres. https://doi.org/10.1103/physreve.69.062901

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