Minimal Projections onto Two Dimensional Subspaces ofl(4)∞

Constants of Strong Unicity of Minimal Projections onto some Two-Dimensional Subspaces of l∞(4)

“…In [2,5,[7][8][9][10][11][12][13] a complete characterization and unicity of minimal projections on hyperplanes and subspaces of codimension two in spaces l 1 ; c 0 and their finite-dimensional analogues l [1,[3][4][5][6]. In this paper we calculate the constants of strong unicity for some twodimensional subspaces in l …”

Codimension-one minimal projections onto Haar subspaces

“…It is worth noting that there exists a large number of papers concerning minimal projections. Mainly the problems of existence [12,15], uniqueness [11,13,25,32,33], characterization of onecomplemented subspaces [1,2,26,30,31], concrete formulas for minimal projections [3][4][5][6][7]10,12,21,22,24,29,34], estimates of the relative projection constants [5,14,19,23,28,31,35], construction of spaces with large relative projection constants [4,5,[16][17][18][19][20], as well as the problems connected with shape-preserving projections [8,9] were considered. For basic information concerning this topic the reader is referred to [27].…”