We formulate a symmetry principle on the basis of the duality of electric and magnetic fields and apply it to dispersion forces. Within the context of macroscopic quantum electrodynamics, we rigorously establish duality invariance for the free electromagnetic field in the presence of causal magnetoelectrics. Dispersion forces are given in terms of the Green tensor for the electromagnetic field ...

Motivated by recent developments on calculus in metric measure spaces (X, d,m), we prove a general duality principle between Fuglede’s notion [15] of p-modulus for families of finite Borel measures in (X, d) and probability measures with barycenter in Lq(X,m), with q dual exponent of p ∈ (1,∞). We apply this general duality principle to study null sets for families of parametric and non-paramet...