Rational curves of minimal degree and characterizations of Pn
نویسنده
چکیده
In this paper we investigate complex uniruled varieties X whose rational curves of minimal degree satisfy a special property. Namely, we assume that the tangent directions to such curves at a general point x ∈ X form a linear subspace of TxX. As an application of our main result, we give a unified geometric proof of Mori’s, Wahl’s, Campana-Peternell’s and Andreatta-Wísniewski’s characterizations of Pn.
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تاریخ انتشار 2004