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Topological swimming in a quantum sea

J. E. Avron·B. Gutkin·D. H. Oaknin
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Abstract

We propose a quantum theory of swimming for swimmers that are small relative to the coherence length of the medium. The quantum swimming equation is derived from known results on quantum pumps. For a one-dimensional Fermi gas at zero temperature we find that swimming is topological: The distance covered in one swimming stroke is quantized in half integer multiples of the Fermi wave length. Moreover, one can swim without dissipation.

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J. E. Avron, B. Gutkin, D. H. Oaknin. 2005-11-20. Topological swimming in a quantum sea. https://doi.org/10.1103/physrevlett.96.130602

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