Spectral Expansions of Homogeneous and Isotropic Tensor-Valued Random Fields

TL;DR

This paper develops spectral expansion methods for homogeneous, isotropic tensor-valued random fields, linking random field theory with convex compacta, applicable to turbulence and material stress modeling.

Contribution

It introduces spectral expansions for tensor-valued random fields in Euclidean space, connecting them with convex compacta theory, a novel approach in the field.

Findings

Spectral expansions for vector-valued random fields established.

Spectral expansions for tensor-valued random fields established.

Link between random fields and convex compacta theory demonstrated.

Abstract

We establish spectral expansions of homogeneous and isotropic random fields taking values in the $3$-dimensional Euclidean space $E^3$ and in the space $\mathsf{S}^2(E^3)$ of symmetric rank $2$ tensors over $E^3$. The former is a model of turbulent fluid velocity, while the latter is a model for the random stress tensor or the random conductivity tensor. We found a link between the theory of random fields and the theory of finite-dimensional convex compacta.