  Let ${\mathfrak g}$ be a Garding-Dirichlet operator on the set S(n) of
symmetric $n\times n$ matrices. We assume that ${\mathfrak g}$ is $I$-central,
that is, $D_I {\mathfrak g} = k I$ for some $k>0$. Then $$ {\mathfrak
g}(A)^{1\over N} \ \geq\ {\mathfrak g}(I)^{1\over N} (\det\, A)^{1\over n}
\qquad \forall\, A>0. $$ From work of Guo, Phong, Tong, Abja, Dinew, Olive and
many others, this inequality has important applications.
