I am looking to solve the following matrix equation for G$G$
GHG - M = 0$$GHG + M = 0$$
where G$G$, H$H$, and M$M$ are square, symmetric, real matrices. H$H$ is negative-definite and M$M$ is positive-definite. G$G$ should also be positive-definite.
Is it possible?
Many thanks!