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arXiv · 2008.11260

Topological Terms and Diffeomorphism Anomalies in Fluid Dynamics and Sigma Models

V. P. Nair
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Abstract

The requirement of diffeomorphism symmetry for the target space can lead to anomalous commutators for the energy-momentum tensor for sigma models and for fluid dynamics, if certain topological terms are added to the action. We analyze several examples . A particular topological term is shown to lead to the known effective hydrodynamics of a dense collection of vortices, i.e. the vortex fluid theory in 2+1 dimensions. The possibility of a similar vortex fluid in 3+1 dimensions, as well as a fluid of knots and links, with possible extended diffeomorphism algebras is also discussed.

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V. P. Nair. 2020-08-25. Topological Terms and Diffeomorphism Anomalies in Fluid Dynamics and Sigma Models. https://doi.org/10.1103/physrevd.103.085017

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