Abstract
AbstractFor a general cubic fourfold $$X\subset \mathbb {P}^5$$
X
⊂
P
5
with Fano variety F, we compute the Hodge numbers of the locus $$S\subset F$$
S
⊂
F
of lines of second type and the class of the locus $$V\subset F$$
V
⊂
F
of triple lines, using the description of the latter in terms of flag varieties. We also give an upper bound of 6 for the degree of irrationality of the Fano scheme of lines of any smooth cubic hypersurface.
Funder
European Research Council
Publisher
Springer Science and Business Media LLC
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