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The geometry of phase mixing

S. Tremaine
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Abstract

Partially phase-mixed structures in galaxies occupy a complex surface of dimension D in six-dimensional phase space. The appearance of such structures to observers is determined by their projection into a subspace whose dimensionality K is determined by the number of observables (e.g. sky position, distance, radial velocity, etc.). We discuss the expected dimensionality of phase-space structures and suggest that the most prominent features in surveys with K=D or K>D will be stable singularities (catastrophes). The simplest of these are the shells seen in the outer parts of elliptical galaxies.

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S. Tremaine. 1998-12-08. The geometry of phase mixing. https://doi.org/10.1046/j.1365-8711.1999.02690.x

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