The Ground State of Ising Model±J on the Tube

A method of linear equations is proposed allowing a reduction of a physical problem of determination of energy, entropy, or magnetisation for the systems with frozen disorder to a mathematical problem of solving a set of linear equations. Apart from an exact method for determination of energy and entropy, a type of the mean field approach is presented, which permits a summation over series representing entropy. Moreover, it was established that magnetisation can appear only when the antiferromagnetic integrals occur at the zero probability.