Criteria for σ-ampleness
| dc.creator | Keeler, Dennis S. | |
| dc.date | 1999-12-06 | |
| dc.date | 2000-02-29 | |
| dc.date.accessioned | 2026-07-07T06:26:55Z | |
| dc.date.available | 2026-07-07T06:26:55Z | |
| dc.description | In the noncommutative geometry of Artin, Van den Bergh, and others, the twisted homogeneous coordinate ring is one of the basic constructions. Such a ring is defined by a $σ$-ample divisor, where $σ$ is an automorphism of a projective scheme X. Many open questions regarding $σ$-ample divisors have remained. We derive a relatively simple necessary and sufficient condition for a divisor on X to be $σ$-ample. As a consequence, we show right and left $σ$-ampleness are equivalent and any associated noncommutative homogeneous coordinate ring must be noetherian and have finite, integral GK-dimension. We also characterize which automorphisms $σ$ yield a $σ$-ample divisor. | |
| dc.description | 16 pages, LaTeX2e, to appear in J. of the AMS, minor errors corrected (esp. in 1.4 and 3.1), proofs simplified | |
| dc.identifier | https://arxiv.org/abs/math/9912051 | |
| dc.identifier | http://arxiv.org/abs/math/9912051 | |
| dc.identifier | J. Amer. Math. Soc. 13 (2000), no. 3, 517-532. | |
| dc.identifier | doi:10.1090/S0894-0347-00-00334-9 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/97261 | |
| dc.subject | Algebraic Geometry | |
| dc.subject | Rings and Algebras | |
| dc.subject | 14A22, 14F17, 14J50, 16P90, 16S38, 16W50 | |
| dc.title | Criteria for σ-ampleness | |
| dc.type | text |