Matrix is the same word as matter. Energy is either potential or work. The field is energy and the matrix. Energy is matter.
I would say that energy and matter transform - and are the effect of matrix (space/time) expansion (inflation).
When the Einstein dream of transmuting the base wood of matter to the pure marble of geometry is achieved then you will see the unification of the fields and "space/time = matter/energy".
IMHO, string theory (and particularly f-Theory) is getting us closer day by day - because the geometry is preeminent.