Let $X$ be an Archimedean Riesz space and $\Cal P(X)$ its Boolean algebra of all band projections, and put $\Cal P_{e}=\{P e:P\in \Cal P(X)\}$ and $\Cal B_{e}=\{x\in X: x\wedge (e-x)=0\}$, $e\in X^+$. $X$ is said to have Weak Freudenthal Property (\text{$\operatorname{WFP}$}) provided that for every $e\in X^+$ the lattice $lin\, \Cal P_{e}$ is order dense in the principal band $e^{d d}$. This notion is compared with strong and weak forms of Freudenthal spectral theorem in Archimedean Riesz spaces, studied by Veksler and Lavrič, respectively. \text{$\operatorname{WFP}$} is equivalent to $X^+$-denseness of $\Cal P_{e}$ in $\Cal B_{e}$ for every $e\in X^+$, and every Riesz space with sufficiently many projections has \text{$\operatorname{WFP}$} (THEOREM).
@article{118535, author = {Marek W\'ojtowicz}, title = {On a weak Freudenthal spectral theorem}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {33}, year = {1992}, pages = {631-643}, zbl = {0777.46006}, mrnumber = {1240185}, language = {en}, url = {http://dml.mathdoc.fr/item/118535} }
Wójtowicz, Marek. On a weak Freudenthal spectral theorem. Commentationes Mathematicae Universitatis Carolinae, Tome 33 (1992) pp. 631-643. http://gdmltest.u-ga.fr/item/118535/
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