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Criterion for Dominance of Directional over Size Fluctuations in Destroying Order

H. Kleinert
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Abstract

For systems exhibiting a second-order phase transition with a spontaneously broken continuous O(N)-symmetry at low temperature, we give a criterion for judging at which temperature T_K long-range directional fluctuations of the order field destroy the order when approaching the critical temperature from below. The temperature T_K lies always significantly below the famous Ginzburg temperature T_G at which size fluctuations of finite range in the order field become important.

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H. Kleinert. 1999-11-22. Criterion for Dominance of Directional over Size Fluctuations in Destroying Order. https://doi.org/10.1103/physrevlett.84.286

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