Nodal quintic threefolds and nodal octic surfaces
نویسندگان
چکیده
منابع مشابه
Nonrational Nodal Quartic Threefolds
The Q-factoriality of a nodal quartic 3-fold implies its non-rationality. We prove that a nodal quartic 3-fold with at most 8 nodes is Q-factorial, and we show that a nodal quartic 3-fold with 9 nodes is not Q-factorial if and only if it contains a plane. However, there are non-rational non-Q-factorial nodal quartic 3-folds in P. In particular, we prove the non-rationality of a general non-Q-fa...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1990
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1990-1021895-0