Abstract
Consider a finite classical polar space of rank \(d\ge 2\) and an integer n with \(0<n<d\). In this paper, it is proved that the set consisting of all subspaces of rank n that contain a given point is a largest Erdős-Ko-Rado set of subspaces of rank n of the polar space. We also show that there are no other Erdős-Ko-Rado sets of subspaces of rank n of the same size.
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Metsch, K. An Erdős-Ko-Rado theorem for finite classical polar spaces. J Algebr Comb 43, 375–397 (2016). https://doi.org/10.1007/s10801-015-0637-7
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DOI: https://doi.org/10.1007/s10801-015-0637-7