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arXiv · 1506.06361

Asymptotics of Jack characters

Piotr Śniady
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Abstract

Jack characters are a one-parameter deformation of the characters of the symmetric groups; a deformation given by the coefficients in the expansion of Jack symmetric functions in the basis of power-sum symmetric functions. We study Jack characters from the viewpoint of the asymptotic representation theory. In particular, we give explicit formulas for their asymptotically top-degree part, in terms of bicolored oriented maps with an arbitrary face structure. We also study their multiplicative structure and their structure constants and we prove that they fulfill approximate factorization property, a convenient tool for proving Gaussianity of fluctuations of random Young diagrams.

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Piotr Śniady. 2015-06-21. Asymptotics of Jack characters. https://doi.org/10.1016/j.jcta.2019.02.020

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