Rigorous bounds for 2D disordered ising models
نویسندگان
چکیده
2014 A method systematically improving the annealed bounds (for the free energy and the ground state energy) is presented and illustrated by the example of disordered Ising models. An optimization procedure leads to new bounds for which the critical behaviour differs from the pure model behaviour. Geometrical effects, such as frustration, can also be included in this method. We obtain simple expressions for the critical lines which agree remarkably well with previously known exact results. J. Physique 47 (1986) 947-953 JUIN 1986, Classification Physics Abstracts 05.50 75.40
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