Kac's Theorem for weighted projective lines
نویسندگان
چکیده
منابع مشابه
Projective Representations I. Projective lines over rings
We discuss representations of the projective line over a ring R with 1 in a projective space over some (not necessarily commutative) field K. Such a representation is based upon a (K,R)-bimodule U . The points of the projective line over R are represented by certain subspaces of the projective space P(K,U ×U) that are isomorphic to one of their complements. In particular, distant points go over...
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I prove two theorems: Let X ⊂ P be a hypersurface and let x ∈ X be a general point. If the set of lines having contact to order k with X at x is of dimension greater than expected, then the lines having contact to order k are actually contained in X. A variety X is said to be covered by lines if there exist a finite number of lines in X passing through a general point. Let X ⊂ P be a variety co...
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ژورنال
عنوان ژورنال: Journal of the European Mathematical Society
سال: 2010
ISSN: 1435-9855
DOI: 10.4171/jems/232