Extreme elements of the unit ball of bilinear operators on \(\ell ^ 2_ 2\)
The authors characterize the extreme points of the unit ball of the sup- normed space of trilinear forms on a two dimensional real Hilbert space in terms of their values on orthonormal bases.
extreme points of the unit ball of the sup-normed space of trilinear forms on a two dimensional real Hilbert space in terms of their values on orthonormal bases
scientific article; zbMATH DE number 4065749