Mathematics – Algebraic Geometry
Scientific paper
1994-06-17
Mathematics
Algebraic Geometry
26 pages, AMS-LaTeX
Scientific paper
A subscheme $X\subset \Bbb P^{n+3}$ of codimension $3$ is {\em Pfaffian} if it is the degeneracy locus of a skew-symmetric map $f:\cal{E}\spcheck(-t) @>>> \cal{E}$ with $\cal{E}$ a locally free sheaf of odd rank on $\Bbb P^{n+3}$. It is shown that a codimension $3$ subscheme $X\subset\Bbb P^{n+3}$ is Pfaffian if and only if it is locally Gorenstein, subcanonical (i.e.\ $\omega_X\cong\cal O_X(l)$ for some integer $l$), and the following parity condition holds: if $n\equiv 0\pmod{4}$ and $l$ is even, then $\chi (\cal O_X (l/2))$ is also even. The paper includes a modern version of the Horrocks correspondence, stated in the language of derived categories. A local analogue of the main theorem is also proved.
No associations
LandOfFree
Pfaffian Subschemes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Pfaffian Subschemes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pfaffian Subschemes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-571487