On projective varieties of dimension $n+k$ covered by $k$-spaces
نویسندگان
چکیده
منابع مشابه
Projective Q-factorial Toric Varieties Covered by Lines
We give a structural theorem for Q-factorial toric varieties covered by lines in P N , and compute their dual defect. This yields a characterization of defective Q-factorial toric varieties in P N. The com-binatorial description of such varieties is used to characterize some finite sets of monomials with discriminant equal to one.
متن کاملJoins of Projective Varieties and Multisecant Spaces
Let X1, . . . ,Xs ⊂ PN , s ≥ 1, be integral varieties. For any integers ki > 0, 1 ≤ i ≤ s, and t ≥ 0 set ~k := (k1, . . . , ks) and ~ X := (X1, . . . ,Xs). Let Sec( ~ X; t,~k) be the set of all linear t-spaces contained in a linear (k1 + · · · + ks − 1)-space spanned by k1 points of X1, k2 points of X2, . . . , ks points of Xs. Here we study some cases where Sec( ~ X ; t,~k) has the expected di...
متن کاملOn invariant notions of Segre varieties in binary projective spaces
Invariant notions of a class of Segre varieties S(m)(2) of PG(2m − 1, 2) that are direct products of m copies of PG(1, 2), m being any positive integer, are established and studied. We first demonstrate that there exists a hyperbolic quadric that contains S(m)(2) and is invariant under its projective stabiliser group GS(m)(2). By embedding PG(2 m − 1, 2) into PG(2m − 1, 4), a basis of the latte...
متن کاملPartitioning Segre varieties and projective spaces
The recent interest both in partitions of finite geometries into other geometric objects and in the classical Segre varieties over finite fields are the background motivation for this paper. More precisely, partitions of Segre varieties into Segre varieties are investigated and the idea of nested partitions is introduced. Other partitions, namely of projective spaces and hyperbolic quadrics, ar...
متن کاملQuantum Dimension and Quantum Projective Spaces
We show that the family of spectral triples for quantum projective spaces introduced by D’Andrea and Da̧browski, which have spectral dimension equal to zero, can be reconsidered as modular spectral triples by taking into account the action of the element K2ρ or its inverse. The spectral dimension computed in this sense coincides with the dimension of the classical projective spaces. The connecti...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Illinois Journal of Mathematics
سال: 2002
ISSN: 0019-2082
DOI: 10.1215/ijm/1258136202