arXiv subjects

Rubén A. Pasmanter

Publications and source records attributed to Rubén A. Pasmanter.

2 recordsLinked to original sources

arXiv2009

Decomposing data sets into skewness modes

We derive the nonlinear equations satisfied by the coefficients of linear combinations that maximize their skewness when their variance is constrained to take a specific value. In order to numerically solve these nonlinear equations we develop a gradient-type flow that preserves the constraint. In combination with the Karhunen-Loève decomposition this leads to a set of orthogonal modes with maximal skewness. For illustration purposes we apply these techniques to atmospheric data; in this case the maximal-skewness modes correspond to strongly localized atmospheric flows. We show how these ideas can be extended, for example to maximal-flatness modes.

physics.data-an↗

arXiv1996

Metric structures of inviscid flows

An intrinsic metric tensor, a flat connexion and the corresponding distance-like function are constructed in the configuration space formed by velocity field {\bf and} the thermodynamic variables of an inviscid fluid. The kinetic-energy norm is obtained as a limiting case; all physical quantities are Galilean invariant. Explicit expressions are given for the case of an ideal gas. The flat connexion is {\bf not} metric-compatible. These results are achieved by applying the formalism of statistical manifolds \cite{amari,otros} to the statistical mechanics of a moving fluid.

chao-dyn↗