English
Related papers

Related papers: Variations of generalised pairs

200 papers

In this paper we investigate boundedness and volumes of generalised pairs, and give applications to usual pairs especially to a class of pairs that we call stable log minimal models. Fixing the dimension and a DCC set controlling…

Algebraic Geometry · Mathematics 2021-04-06 Caucher Birkar

It is conjectured that the canonical models of varieties (not of general type) are bounded when the Iitaka volume is fixed. We confirm this conjecture when the general fibers of the corresponding Iitaka fibration are in a fixed bounded…

Algebraic Geometry · Mathematics 2025-09-17 Junpeng Jiao

We investigate the DCC property of the set of Iitaka volumes of a given set of pairs of varieties. We both generalize previous results of Birkar and Li about usual pairs to the real coefficient case, and also establish similar results on…

Algebraic Geometry · Mathematics 2026-05-19 Pinxian Bie

In this paper, we investigate the boundedness of log pairs with log Calabi--Yau fibration structures. We prove that total spaces of log Calabi--Yau fibrations are bounded modulo crepant birational equivalence when the Iitaka volumes of log…

Algebraic Geometry · Mathematics 2025-06-13 Junpeng Jiao

We investigate the boundedness problem for log Calabi-Yau fibrations whose bases and general fibers are bounded. We prove that the total spaces of log Calabi-Yau fibrations are bounded in codimension one after fixing some natural…

Algebraic Geometry · Mathematics 2025-04-08 Xiaowei Jiang , Junpeng Jiao , Minzhe Zhu

In this note, we survey some recent developments in birational geometry concerning the boundedness of algebraic varieties. We delineate a strategy to extend some of these results to the case of generalized pairs, first introduced by Birkar…

Algebraic Geometry · Mathematics 2022-03-02 Stefano Filipazzi , Roberto Svaldi

In this paper, we study the behavior of the sets of volumes of the form $\mathrm{vol}(X,K_X+B+M)$, where $(X,B)$ is a log canonical pair, and $M$ is a nef $\mathbb{R}$-divisor. After a first analysis of some general properties, we focus on…

Algebraic Geometry · Mathematics 2021-08-12 Stefano Filipazzi

For every smooth complex projective variety $W$ of dimension $d$ and nonnegative Kodaira dimension, we show the existence of a universal constant $m$ depending only on $d$ and two natural invariants of the very general fibres of an Iitaka…

Algebraic Geometry · Mathematics 2018-09-24 Caucher Birkar , De-Qi Zhang

We study the birational boundedness of special fibers of log Calabi-Yau fibrations and Fano fibrations. We show that for a locally stable family of Fano varieties or polarised log Calabi-Yau pairs over a curve, if the general fiber…

Algebraic Geometry · Mathematics 2023-02-17 Junpeng Jiao

We show that the family of semi log canonical pairs with ample log canonical class and with fixed volume is bounded.

Algebraic Geometry · Mathematics 2017-09-22 Christopher Hacon , James McKernan , Chenyang Xu

In this paper, we construct counterexamples to the boundedness of generalised log canonical models of surfaces with fixed appropriate invariants, where the underlying varieties can have arbitrary Kodaira dimension. This answers a question…

Algebraic Geometry · Mathematics 2025-04-10 Christopher Hacon , Xiaowei Jiang

We show the existence of $n$-complements for generalized pairs with additional Diophantine approximation properties when the coefficients of boundaries belong to a DCC set.

Algebraic Geometry · Mathematics 2020-08-10 Guodu Chen

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

We prove that normal projective stable families of maximal variation, of fixed dimension, and with bounded adjoint volume are birationally bounded. This is a consequence of a substantially stronger statement, formulated a priori…

Algebraic Geometry · Mathematics 2026-04-28 Paolo Cascini , Jihao Liu , Calum Spicer , Roberto Svaldi

We study the relationship between Iitaka fibrations and the conjecture on the existence of complements, assuming the good minimal model conjecture. In one direction, we show that the conjecture on the existence of complements implies the…

Algebraic Geometry · Mathematics 2023-01-13 Guodu Chen , Jingjun Han , Jihao Liu

We study lc pairs polarized by a nef and log big divisor. After proving the minimal model theory for projective lc pairs polarized by a nef and log big divisor, we prove the effectivity of the Iitaka fibrations and some boundedness results…

Algebraic Geometry · Mathematics 2022-10-11 Kenta Hashizume

It is conjectured that the base varieties of the Iitaka fibrations are bounded when the Iitaka volumes are bounded above. We confirm this conjecture for Iitaka $\epsilon$-lc Fano type fibrations.

Algebraic Geometry · Mathematics 2023-01-26 Zhan Li

We survey recent results on the boundedness of the moduli functor of stable pairs

Algebraic Geometry · Mathematics 2017-09-22 Christopher D. Hacon , James McKernan , Chenyang Xu

We show that fixed dimensional klt weak Fano pairs with alpha-invariants and volumes bounded away from $0$ and the coefficients of the boundaries belonging to a fixed DCC set $S$ form a bounded family. Moreover, such pairs admit a strong…

Algebraic Geometry · Mathematics 2020-02-25 Weichung Chen

We show boundedness of polarized Calabi--Yau fibrations over curves only with fixed volumes of general fibers and Iitaka volumes. As its application, we construct a separated coarse moduli space of K-stable Calabi-Yau fibrations over curves…

Algebraic Geometry · Mathematics 2025-06-11 Kenta Hashizume , Masafumi Hattori
‹ Prev 1 2 3 10 Next ›