TY - JOUR
T1 - Explicit models of ℓ_1-preduals and the weak* fixed point property in ℓ_1
AU - Casini, Emanuele
AU - Miglierina, Enrico
AU - Piasecki, Lukasz
PY - 2024
Y1 - 2024
N2 - We provide a concrete isometric description of all the preduals of $\ell_1$ for which the standard basis in $\ell_1$ has a finite number of $w^*$-limit points. Then, we apply this result to give an example of an $\ell_1$-predual $X$ such that its dual $X^*$ lacks the weak$^*$ fixed point property for nonexpansive mappings (briefly, $w^*$-FPP), but $X$ does not contain an isometric copy of any hyperplane $W_{\alpha}$ of the space $c$ of convergent sequences such that $W_\alpha$ is a predual of $\ell_1$ and $W_\alpha^*$ lacks the $w^*$-FPP. This answers a question left open in the 2017 paper of the present authors.
AB - We provide a concrete isometric description of all the preduals of $\ell_1$ for which the standard basis in $\ell_1$ has a finite number of $w^*$-limit points. Then, we apply this result to give an example of an $\ell_1$-predual $X$ such that its dual $X^*$ lacks the weak$^*$ fixed point property for nonexpansive mappings (briefly, $w^*$-FPP), but $X$ does not contain an isometric copy of any hyperplane $W_{\alpha}$ of the space $c$ of convergent sequences such that $W_\alpha$ is a predual of $\ell_1$ and $W_\alpha^*$ lacks the $w^*$-FPP. This answers a question left open in the 2017 paper of the present authors.
KW - Nonexpansive mappings, w-fixed point property, Lindenstrauss spaces
KW - Nonexpansive mappings, w-fixed point property, Lindenstrauss spaces
UR - http://hdl.handle.net/10807/272908
UR - https://apcz.umk.pl/tmna/article/view/49317
U2 - 10.12775/tmna.2023.009
DO - 10.12775/tmna.2023.009
M3 - Article
SN - 1230-3429
VL - 63
SP - 39
EP - 51
JO - Topological Methods in Nonlinear Analysis
JF - Topological Methods in Nonlinear Analysis
ER -