Beschreibung:
<jats:title>Abstract</jats:title>
<jats:p> Sturm oscillation theorem for second order differential equations was generalized to systems and higher order equations with positive leading coefficient by several authors. What we propose here is a Sturm type oscillation theorem for indefinite systems with Dirichlet boundary conditions of the form</jats:p>
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<jats:p>where p<jats:sub>i</jats:sub> is a smooth path of matrices on the complex n-dimensional vector space ℂ<jats:sup>n</jats:sup>, p<jats:sub>2m</jats:sub> is the symmetry represented by the diagonal block matrix diag (I<jats:sub>n-v, </jats:sub>-I<jats:sub>v</jats:sub>), and where v is an integer between 0 and n and I is the identity matrix.</jats:p>