%0 Journal Article
%T Representation theorems with variables in an intrinsic form
%A Sebastiano Pennisi
%J Le Matematiche
%D 1989
%I University of Catania
%X In a Minkowski space V, consideration is given to the tensor-valued isotropic functions of an arbitrary number of tensors of which one is a time-like vector U¦Á and another is a symmetric tensor A¦Á¦Â,  such that  ¦Á¦Â, its space-space part orthogonal to U¦Á, has distinct eigenvalues. Representations are given for these functions in terms of an orthonormal basis of eigenvectors UA ¦Á of   ¦Á¦Â (A=0,1,2,3). The relationship between the total and the partial derivative of these function with respect to the independent components of UA ¦Á  is also obtained in covariant form.
%U http://www.dmi.unict.it/ojs/index.php/lematematiche/article/view/695