# On biorthogonal systems whose functionals are finitely supported

@article{Brech2010OnBS, title={On biorthogonal systems whose functionals are finitely supported}, author={Christina Brech and Piotr Koszmider}, journal={arXiv: Functional Analysis}, year={2010} }

We show that for each natural $n>1$ it is consistent that there is a compact Hausdorff space $K_{2n}$ such that in $C(K_{2n})$ there is no uncountable (semi)biorthogonal sequence $(f_\xi,\mu_\xi)_{\xi\in \omega_1}$ where $\mu_\xi$'s are atomic measures with supports consisting of at most $2n-1$ points of $K_{2n}$, but there are biorthogonal systems $(f_\xi,\mu_\xi)_{\xi\in \omega_1}$ where $\mu_\xi$'s are atomic measures with supports consisting of $2n$ points. This complements a result of…

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