Implement Shirokov's arbitrary metric inverse

[hugohadfield]

This should hopefully allow us to extend the current linalg free inverse method to arbitrary algebras, details in this paper: https://arxiv.org/pdf/2005.04015.pdf

[hugohadfield]

Specifically Theorem 4 on page 16 looks like the section we might think about implementing

[donhatch]

Specifically Theorem 4 on page 16 looks like the section we might think about implementing

Good job finding the (surprisingly short) algorithm buried in the Shirokov paper; I couldn't even find it until I saw your comment above.

And maybe it's equivalent to what is described in Theorem 3 on page 4 of this other more recent paper? (It's not completely clear to me yet):

Dimiter Prodanov "Algorithmic computation of multivector inverses and characteristic polynomials in non-degenerate Clifford algebras"
https://vixra.org/pdf/2306.0009v1.pdf