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<mrnumber>MR2976045</mrnumber>
<author>Seiichiro WAKABAYASHI</author>
<author_utf8>Seiichiro WAKABAYASHI</author_utf8>
<title>On the Cauchy Problem for Second-Order Hyperbolic Operators with the Coefficients of Their Principal Parts Depending Only on the Time Variable</title>
<journal>Funkcialaj Ekvacioj. Serio Internacia</journal>
<volume>55</volume>
<year>2012</year>
<page>99--136</page>
<url_pdf>http://fe.math.kobe-u.ac.jp/FE/FullPapers/55-1/55_99.pdf</url_pdf>
<mathsci_link>http://www.ams.org/mathscinet-getitem?mr=MR2976045</mathsci_link>
<abstract>We investigate the Cauchy problem for second-order hyperbolic operators in the framework of the space of $C^\infty $ functions. In the case where the coefficients of their principal parts depend only on the time variable and are real analytic, we give a sufficient condition for $C^\infty $ well-posedness, which is also a necessary one when the space dimension is less than $3$ or the coefficients of the principal parts are semi-algebraic functions (e.g., polynomials) of the time variable.</abstract>
<keywords>Cauchy problem, Hyperbolic, $C^\infty$ well-posed, Second order.</keywords>
<subject>Primary 35L15; Secondary 35L10.</subject>
<fesi_info>
  <FILE>55-99</FILE>
  <YEAR>2012</YEAR>
  <TITLE>On the Cauchy Problem for Second-Order Hyperbolic Operators with the Coefficients of Their Principal Parts Depending Only on the Time Variable</TITLE>
  <AUTHOR>Seiichiro WAKABAYASHI</AUTHOR>
  <AUTHOR_utf8>Seiichiro WAKABAYASHI</AUTHOR_utf8>
</fesi_info>

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