Thus the bimetrically spherically symmetric covariant tensor
In particular, we are interesting in the sub-module consisting of the covariant tensor
fields of degree 2.
Furthermore, we need an anti-symmetric, covariant tensor
which is non-degenerate.
This metric observable tensor, in real observations where the observer accompanies his references, is the same that the analogous built general covariant tensor
Besides, there is an obstacle related to definition of observable components of covariant tensors
(in which the indices are subscripts) and of mixed tensors, which have both subscripts and superscripts.