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Symmetries in the fourth Painlevé equation and Okamoto polynomials

Published online by Cambridge University Press:  22 January 2016

Masatoshi Noumi
Affiliation:
Department of Mathematics, Kobe University Rokko, Kobe 657-8501, Japan, noumi@math.kobe-u.ac.jp
Yasuhiko Yamada
Affiliation:
Department of Mathematics, Kobe University Rokko, Kobe 657-8501, Japan, yamaday@math.kobe-u.ac.jp
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Abstract

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The fourth Painlevé equation PIV is known to have symmetry of the affine Weyl group of type with respect to the Bäcklund transformations. We introduce a new representation of PIV, called the symmetric form, by taking the three fundamental invariant divisors as the dependent variables. A complete description of the symmetry of PIV is given in terms of this representation. Through the symmetric form, it turns out that PIV is obtained as a similarity reduction of the 3-reduced modified KP hierarchy. It is proved in particular that the special polynomials for rational solutions PIV, called Okamoto polynomials, are expressible in terms of the 3-reduced Schur functions.

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 1999

References

[1] Fukutani, S., Okamoto, K. and Umemura, H., Special polynomials associated with the rational solutions and the Hirota bilinear relations of the 2nd and the 4th Painlevé equations, preprint.Google Scholar
[2] Jimbo, M. and Miwa, T., Solitons and infinite dimensional Lie algebras, Publ. RIMS, Kyoto Univ., 19 (1983), 9431001.CrossRefGoogle Scholar
[3] Kac, M. and van Moerbeke, P., On an explicitly soluble system of nonlinear differential equations related to certain Toda lattices, Advances Math., 16 (1975), 160169.CrossRefGoogle Scholar
[4] Murata, Y., Rational solutions of the second and the fourth equations of Painlevé, Funkcialaj Ekvacioj, 28 (1985), 132.Google Scholar
[5] Nishitani, T. and Tajiri, M., On similarity solutions of Boussinesq equation, Phys. Lett., 89A (1982), 379380.CrossRefGoogle Scholar
[6] Noumi, M. and Okamoto, K., Irreducibility of the second and the fourth Painlevé equations, Funkcialaj Ekvacioj, 40 (1997), 139163.Google Scholar
[7] Okamoto, K., Studies on Painlevé equations III, Second and fourth Painlevé equations PII and PIV , Math. Ann., 275 (1986), 221255.CrossRefGoogle Scholar
[8] Okamoto, K., Algebraic relations among six adjacent τ-functions related to the fourth Painlevé system, Kyushu J. Math., 50 (1996), 513532.CrossRefGoogle Scholar
[9] Umemura, H., On the irreducibility of the first differential equations of Painlevé.CrossRefGoogle Scholar
[10] Quispel, G. R. W., Nijhoff, F.W. and Capel, H. W., Linearization of the Boussinesqequation and the modified Boussinesq equation, Phys. Lett., 91A (1982), 143145.CrossRefGoogle Scholar