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Ray helicity: a geometric invariant for multi-dimensional resonant wave conversion

E. R. Tracy·A. N. Kaufman
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Abstract

For a multicomponent wave field propagating into a multidimensional conversion region, the rays are shown to be helical, in general. For a ray-based quantity to have a fundamental physical meaning it must be invariant under two groups of transformations: congruence transformations (which shuffle components of the multi-component wave field) and canonical transformations (which act on the ray phase space). It is shown that for conversion between two waves there is a new invariant not previously discussed: the intrinsic helicity of the ray.

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BibTeXRIS

E. R. Tracy, A. N. Kaufman. 2003-03-20. Ray helicity: a geometric invariant for multi-dimensional resonant wave conversion. https://doi.org/10.1103/physrevlett.91.130402

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