Open Access
2010 Note on extreme points in Marcinkiewicz function spaces
Anna Kaminska , Anca M. Parrish
Banach J. Math. Anal. 4(1): 1-12 (2010). DOI: 10.15352/bjma/1272374667
Abstract

We show that the unit ball of the subspace $M_W^0$ of ordered continuous elements of $M_W$ has no extreme points, where $M_W$ is the Marcinkiewicz function space generated by a decreasing weight function $w$ over the interval $(0,\infty)$ and $W(t) = \int_0^tw$, $t\in(0,\infty)$. We also present here a proof of the fact that a function $f$ in the unit ball of $M_W$ is an extreme point if and only if $f^*=w$.

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Copyright © 2010 Tusi Mathematical Research Group
Anna Kaminska and Anca M. Parrish "Note on extreme points in Marcinkiewicz function spaces," Banach Journal of Mathematical Analysis 4(1), 1-12, (2010). https://doi.org/10.15352/bjma/1272374667
Published: 2010
Vol.4 • No. 1 • 2010
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