Line-Bundle-Valued Ternary Quadratic Bundles Over Schemes
| dc.creator | Eesanaipaadi, Venkata Balaji Thiruvalloor | |
| dc.date | 2005-06-08 | |
| dc.date | 2005-07-24 | |
| dc.date.accessioned | 2026-07-07T05:20:36Z | |
| dc.date.available | 2026-07-07T05:20:36Z | |
| dc.description | We describe a satisfactory theory of degeneration of quadratic forms in three variables in the most general setting possible: the quadratic forms are defined on rank 3 vector bundles over an arbitrary scheme and could have values in nontrivial line bundles. Our results extend what is known for good forms; for example we show that the Witt-invariant suffices for classification. We determine explicitly the general, special and usual orthogonal groups and present applications. We indicate examples of rank 4 vector bundles that do not admit any Azumaya structures and of rank 3 vector bundles that do not admit any good quadratic forms with values in specified line bundles. These examples occur naturally on the Seshadri-desingularisations of moduli spaces of rank two degree zero vector bundles over a curve relative to an integral normal locally-Nagata (universally Japanese) base scheme. | |
| dc.description | 79 pages; PDFLaTeX; improved exposition; new result included--isomorphism of the Picard group of the base with that of the scheme of specialised algebras; some typos and cross-references corrected | |
| dc.identifier | https://arxiv.org/abs/math/0506146 | |
| dc.identifier | http://arxiv.org/abs/math/0506146 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/75436 | |
| dc.subject | Algebraic Geometry | |
| dc.subject | Rings and Algebras | |
| dc.subject | 14A25, 14F05, 14L15, 14M, 14Q, 15A63, 15A66, 15A75, 15A78, 16H05, 16S60, 16W20, 20G05, 20G35 | |
| dc.title | Line-Bundle-Valued Ternary Quadratic Bundles Over Schemes | |
| dc.type | text |