Where do homogeneous polynomials on l1n attain their norm?

نویسندگان

  • David Pérez-García
  • Ignacio Villanueva
چکیده

Using a ‘reasonable’ measure in P(`1 ), the space of 2homogeneous polynomials on `1 , we show the existence of a set of positive (and independent of n) measure of polynomials which do not attain their norm in the vertices of the unit ball of `1 . Next we prove that, when n grows, the measure of the set of polynomials which attain their norm in a face of ‘high’ dimension of the unit ball tends to 0.

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عنوان ژورنال:
  • Journal of Approximation Theory

دوره 127  شماره 

صفحات  -

تاریخ انتشار 2004