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arXiv · 1510.05443

Poincaré-like approach to Landau Theory. I. General theory

G. Gaeta
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Abstract

We discuss a procedure to simplify the Landau potential, based on Michel's reduction to orbit space and Poincaré normalization procedure; and illustrate it by concrete examples. The method makes use, as in Poincaré theory, of a chain of near-identity coordinate transformations with homogeneous generating functions; using Michel's insight, one can work in orbit space. It is shown that it is possible to control the choice of generating functions so to obtain a (in many cases, substantial) simplification of the Landau polynomial, including a reduction of the parameters it depends on. Several examples are considered in detail.

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G. Gaeta. 2015-10-19. Poincaré-like approach to Landau Theory. I. General theory. https://doi.org/10.1063/1.4927425

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