-- Basic idea: infinite resitance, conductive exist. Is there a way
-- to represent conductivity/resistance as a projective entity?
-- Primal/dual, projective?
-- conductive: G I = V
-- resistivie: R V = I
-- projective: A I + B V = 0 (or A [I,V] = 0 ?)
--
-- If either G or R is not full rank, the inverse "view" is not
-- correct. Questions: does it really matter? Infinities arise only
-- when infinite resitance, conductance appears.