Effective basepoint-free theorem for semi-log canonical surfaces

Abstract

This paper proposes a Fujita-type freeness conjecture for semi-log canonical pairs. We prove it for curves and surfaces by using the theory of quasi-log schemes and give some effective very ampleness results for stable surfaces and semi-log canonical Fano surfaces. We also prove an effective freeness for log surfaces.

15 pages, v2: Section 7 is new, v3: minor modifications, v4: revision following referee's comments. arXiv admin note: text overlap with arXiv:1401.4332; text overlap with arXiv:1601.01028 by other authors

References in corpus (2)

• Effective base point free theorem for log canonical pairs--Kollár type theorem
• The Angehrn-Siu Type Effective Freeness For Quasi-Log Canonical Pairs

Cited by in corpus (2)

• Injectivity theorem for pseudo-effective line bundles and its applications
• The Angehrn-Siu Type Effective Freeness For Quasi-Log Canonical Pairs