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arXiv · 2305.13737

Symplectic Symmetry and Radial Symmetry Either Persistence or Breaking of Incompressible Fluid

Yongqian Han
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Abstract

The incompressible Navier-Stokes equations are considered. We find that these equations have symplectic symmetry structures. Two linearly independent symplectic symmetries form moving frame. The velocity vector possesses symplectic representation in a moving frame. The symplectic representation of two-dimensional Navier-Stokes equations holds radial symmetry persistence. On the other hand, we establish some results of radial symmetry either persistence or breaking for the symplectic representations of three-dimensional Navier-Stokes equations. Thanks radial symmetry persistence, we construct infinite non-trivial solutions of static Euler equations with given boundary condition.

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Yongqian Han. 2023-05-23. Symplectic Symmetry and Radial Symmetry Either Persistence or Breaking of Incompressible Fluid. https://arxiv.org/abs/2305.13737

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