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Discrete approximations to vector spin models

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 Added by Christof Kuelske
 Publication date 2011
  fields Physics
and research's language is English




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We strengthen a result of two of us on the existence of effective interactions for discretised continuous-spin models. We also point out that such an interaction cannot exist at very low temperatures. Moreover, we compare two ways of discretising continuous-spin models, and show that, except for very low temperatures, they behave similarly in two dimensions. We also discuss some possibilities in higher dimensions.



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