Popis: |
For $1\leq p\leq q\leq\infty$ and a locally convex space $E$, we introduce and study the $(V^\ast)$ subsets of order $(p,q)$ of $E$ and the $(V)$ subsets of order $(p,q)$ of the topological dual $E'$ of $E$. Using these sets we define and study the (sequential) Pe{\l}czy\'{n}ski's property $V^\ast$ of order $(p,q)$, the (sequential) Pe{\l}czy\'{n}ski's property $V$ of order $(p,q)$, and the Pe{\l}czy\'{n}ski's property $(u)$ of order $p$ in the class of all locally convex spaces. To this end, we also introduce and study several new completeness type properties, weak barrelledness conditions, Schur type properties, the Gantmacher property for locally convex spaces, and $(q,p)$-summing operators between locally convex spaces. Applications to some classical function spaces are given. |