Momentum and pseudomomentum in a shallow water equation

J. A. Hanna

doi:10.1063/5.0120645

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arXiv · 2208.05657

Momentum and pseudomomentum in a shallow water equation

J. A. Hanna

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Abstract

A basic shallow water system with variable topography is analyzed from the point of view of a Lagrangian derivation of momentum, energy, and pseudomomentum balances. A two-dimensional action and associated momentum equation are derived. The latter is further manipulated to derive additional equations for energy and pseudomomentum. This revealed structure emphasizes broken symmetries in space and a reference configuration, and preserved symmetry in time.

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J. A. Hanna. 2022-08-11. Momentum and pseudomomentum in a shallow water equation. https://doi.org/10.1063/5.0120645

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