Kramers-Wannier Duality and Random Bond Ising Model

We present a new combinatorial approach to the Ising model incorporating arbitrary bond weights on planar graphs. In contrast to existing methodologies, the exact free energy is expressed as the determinant of a set of ordered and disordered operators defined on vertices and dual vertices respectively, thereby explicitly demonstrating the Kramers-Wannier duality. The implications of our derived formula for the random bond Ising model are further elucidated.