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Emergence of a singularity for Toeplitz determinants and Painleve V

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 نشر من قبل Tom Claeys
 تاريخ النشر 2010
  مجال البحث فيزياء
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We obtain asymptotic expansions for Toeplitz determinants corresponding to a family of symbols depending on a parameter $t$. For $t$ positive, the symbols are regular so that the determinants obey SzegH{o}s strong limit theorem. If $t=0$, the symbol possesses a Fisher-Hartwig singularity. Letting $tto 0$ we analyze the emergence of a Fisher-Hartwig singularity and a transition between the two different types of asymptotic behavior for Toeplitz determinants. This transition is described by a special Painleve V transcendent. A particular case of our result complements the classical description of Wu, McCoy, Tracy, and Barouch of the behavior of a 2-spin correlation function for a large distance between spins in the two-dimensional Ising model as the phase transition occurs.



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