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Critical behavior of n-vector model with quenched randomness

J. Kaupuzs
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Abstract

We consider the Ginzburg-Landau phase transition model with O(n) symmetry (i.e., the n-vector model) which includes a quenched randomness, i.e., a random temperature disorder. We have proven rigorously that within the diagrammatic perturbation theory the quenched randomness does not change the critical exponents at n tending to 0, which is in contrast to the conventional point of view based on the perturbative renormalization group theory.

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J. Kaupuzs. 2000-02-13. Critical behavior of n-vector model with quenched randomness. https://arxiv.org/abs/cond-mat/0002149

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