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The action of pseudo-differential operators on functions harmonic outside a smooth hyper-surface

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 نشر من قبل Yves Colin de Verdiere
 تاريخ النشر 2012
  مجال البحث فيزياء
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We consider a smooth hyper-surface Z of a closed Riemannian manifold X. Let P be the Poisson operator associating to a smooth function on Z its harmonic extension on XZ. If A is a pseudo-differential operator on X of degree <3, we prove that B=P^* A P is a pseudo-differential operator on Z and calculate the principal symbol of B.



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