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<mrnumber>MR2428827</mrnumber>
<author>Yoshishige HARAOKA and Youichi UENO</author>
<author_utf8>Yoshishige HARAOKA and Youichi UENO</author_utf8>
<title>Rigidity for Appell's Hypergeometric Series $F_4$</title>
<journal>Funkcialaj Ekvacioj. Serio Internacia</journal>
<volume>51</volume>
<year>2008</year>
<page>149--164</page>
<url_pdf>http://fe.math.kobe-u.ac.jp/FE/FullPapers/51-1/51_149.pdf</url_pdf>
<mathsci_link>http://www.ams.org/mathscinet-getitem?mr=MR2428827</mathsci_link>
<abstract>Appell's hypergeometric series $F_4$ defines a multi-valued function in ${\bf P}^2{\bf C}\setminus L$ with some hypersurface $L$, and then defines a local system over it. We show that the local system is physically rigid. Using this fact, we get a monodromy representation of $F_4$ without using any analytic expression such as integral expression of $F_4$. A condition for the irreducibility of the monodromy group is obtained. Relations to rigidity of several sections are considered.</abstract>
<keywords>Hypergeometric series, Monodromy, Rigidity.</keywords>
<subject>33C65.</subject>
<fesi_info>
  <FILE>51-149</FILE>
  <YEAR>2008</YEAR>
  <TITLE>Rigidity for Appell's Hypergeometric Series $F_4$</TITLE>
  <AUTHOR>Yoshishige HARAOKA and Youichi UENO</AUTHOR>
  <AUTHOR_utf8>Yoshishige HARAOKA and Youichi UENO</AUTHOR_utf8>
</fesi_info>

<references>

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