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Understanding critical behavior in the framework of the extended equilibrium fluctuation theorem

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 نشر من قبل Luisberis Velazquez-Abad
 تاريخ النشر 2012
  مجال البحث فيزياء
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Recently (arXiv:0910.2870), we have derived a fluctuation theorem for systems in thermodynamic equilibrium compatible with anomalous response functions, e.g. the existence of states with textit{negative heat capacities} $C<0$. In this work, we show that the present approach of the fluctuation theory introduces new insights in the understanding of textit{critical phenomena}. Specifically, the new theorem predicts that the environmental influence can radically affect critical behavior of systems, e.g. to provoke a suppression of the divergence of correlation length $xi$ and some of its associated phenomena as spontaneous symmetry breaking. Our analysis reveals that while response functions and state equations are emph{intrinsic properties} for a given system, critical behaviors are always emph{relative phenomena}, that is, their existence crucially depend on the underlying environmental influence.

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