Une minoration de la norme de l’opérateur de Cauchy sur les graphes lipschitziens

Abstract

It was shown by T. Murai that the norm of the operator defined by the Cauchy kernel on the graph of a Lipschitz function A A is less than C ( 1 + ‖ A ′ ‖ ∞ ) 1 / 2 C{(1 + {\left \| {A’} \right \|_\infty })^{1/2}} . We use Garnett’s example to show that this estimate is optimal.