Some applications of Q-points and Lebesgue filters to Banach spaces
DOI:
https://doi.org/10.17398/Keywords:
Q-point, Katětov order, L-sequence, L-elementAbstract
We present a new characterization of Q-point ultrafilters and use it to optimize the result of Avilés, Martı́nez-Cervantes, and Rueda Zoca linking the existence of L-orthogonal sequences and L-orthogonal elements in Banach spaces via ultrafilter limits.
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