English
Related papers

Related papers: Base point free theorems--saturation, b-divisors, …

200 papers

We prove a base point free theorem for nef and log big divisors on log canonical surfaces.

alg-geom · Mathematics 2008-02-03 Shigetaka Fukuda

We prove the base point free theorem for big line bundles on a three-dimensional log canonical projective pair defined over the algebraic closure of a finite field.

Algebraic Geometry · Mathematics 2016-01-20 Diletta Martinelli , Yusuke Nakamura , Jakub Witaszek

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…

Algebraic Geometry · Mathematics 2017-01-26 Osamu Fujino

We prove Koll\'ar's effective base point free theorem for log canonical pairs.

Algebraic Geometry · Mathematics 2009-07-13 Osamu Fujino

This treats the base-point-freeness of the adjoint bundles on normal surfaces with a boundary. This is an extension of the non-relative version of the theorem of Ein-Lazarsfeld-Masek and the theorem of Kawachi-Masek.

alg-geom · Mathematics 2008-02-03 Takeshi Kawachi

We prove Angehrn-Siu type effective base point freeness and point separation for log canonical pairs.

Algebraic Geometry · Mathematics 2009-11-13 Osamu Fujino

We give the new effective criterion for the global generation of the adjoint bundle on normal surfaces with a boundary. We could make the invariant \delta small a bit more on log-terminal singular point, and then we could prove the theorem…

Algebraic Geometry · Mathematics 2007-05-23 Takeshi Kawachi

We obtain a correct generalization of Shokurov's non-vanishing theorem for log canonical pairs. It implies the base point free theorem for log canonical pairs. We also prove the rationality theorem for log canonical pairs. As a corollary,…

Algebraic Geometry · Mathematics 2009-12-01 Osamu Fujino

Let $(X,\Delta)$ be a proper dlt pair and $L$ a nef Cartier divisor such that $aL-(K_X+\Delta)$ is nef and log big on $(X,\Delta)$ for some $a\in {\mathbb Z}_{>0}$. Then $|mL|$ is base point free for every $m\gg 0$.

Algebraic Geometry · Mathematics 2007-05-23 Osamu Fujino

We establish the generalized canonical bundle formula for generalized lc-trivial fibrations with irrational coefficients over non-compact bases in the complex analytic setting, and we show that the discriminant b-divisor and moduli…

Algebraic Geometry · Mathematics 2026-05-05 Kenta Hashizume

The authors and D. Martinelli proved the base point free theorem for big line bundles on a three-dimensional log canonical projective pair defined over the algebraic closure of a finite field. In this paper, we drop the bigness condition…

Algebraic Geometry · Mathematics 2024-04-30 Yusuke Nakamura , Jakub Witaszek

We prove Koll\'ar-type effective basepoint-free theorems for quasi-log canonical pairs.

Algebraic Geometry · Mathematics 2016-11-24 Osamu Fujino

Working in point-free topology under the constraints of geometric logic, we prove the Fundamental Theorem of Calculus, and apply it to prove the usual rules for the derivatives of $x^\alpha$, $\gamma^x$, and $\log_\gamma x$.

Category Theory · Mathematics 2023-12-11 Steven Vickers

In this paper, we investigate higher direct images of log canonical divisors. After we reformulate Koll\'ar's torsion-free theorem, we treat the relationship between higher direct images of log canonical divisors and the canonical…

Algebraic Geometry · Mathematics 2007-05-23 Osamu Fujino

We prove a canonical bundle formula for generically finite morphisms in the setting of generalized pairs (with $\mathbb{R}$-coefficients). This complements Filipazzi's canonical bundle formula for morphisms with connected fibres. It is then…

Algebraic Geometry · Mathematics 2020-11-19 Jingjun Han , Wenfei Liu

We survey foundational principles of Grothendieck's generalized spaces, including a critical glossary of the various, and often conflicting, terminological usages. Known results using generalized points support a fully pointwise notation…

Category Theory · Mathematics 2022-06-03 Steven Vickers

We prove the base point free theorem for log canonical foliated pairs of rank one on a Q-factorial projective klt threefold. Moreover, we show abundance in the case of numerically trivial log canonical foliated pairs of rank one in any…

Algebraic Geometry · Mathematics 2026-01-21 Paolo Cascini , Calum Spicer

We formulate a conjecture on the behavior of the minimal free resolutions of sets of general points on arbitrary varieties embedded by complete linear series, in analogy with the well-known Minimal Resolution Conjecture for points in…

Algebraic Geometry · Mathematics 2007-05-23 Gavril Farkas , Mircea Mustata , Mihnea Popa

We consider a canonical bundle formula for generically finite proper surjective morphisms and obtain subadjunction formulae for minimal log canonical centers of log canonical pairs. We also treat related topics and applications.

Algebraic Geometry · Mathematics 2010-09-22 Osamu Fujino , Yoshinori Gongyo

We prove a logarithmic base change theorem for pushforwards of pluri-canonical bundles and use it to deduce that positivity properties of log canonical divisors descend via smooth projective morphisms. As an application, for a surjective…

Algebraic Geometry · Mathematics 2026-03-25 Sung Gi Park
‹ Prev 1 2 3 10 Next ›