Is there a succinct way to denote that all eigenvalues of a matrix $A$ have negative real parts?
If the eigenvalues were real, I could simply write this as $$-1 < A < +1$$ since we have the standard definition of matrix inequality $$A < B \equiv x^\top A x < A^\top B x\ \ \forall x$$ but what about the case when the eigenvalues might be complex?