English
Related papers

Related papers: On termination of log flips in dimension four

200 papers

Let $f:X\to Y$ be an algebraic fiber space with general fiber $F$. If $Y$ is of maximal Albanese dimension, we show that $\kappa (X)\geq \kappa (Y)+\kappa (F)$.

Algebraic Geometry · Mathematics 2015-05-19 Jungkai Alfred Chen , Christopher D. Hacon

We prove the existence of flips for $\mathbb Q$-factorial NQC generalized lc pairs, and the cone and contraction theorems for NQC generalized lc pairs. This answers a question of C. Birkar which was conjectured by J. Han and Z. Li. As an…

Algebraic Geometry · Mathematics 2021-09-10 Christopher D. Hacon , Jihao Liu

We provide infinitely many examples of pairs of diffeomorphic, non simply connected K\" ahler manifolds of complex dimension three with different Kodaira dimensions. Also, in any possible Kodaira dimension we find infinitely many pairs of…

Differential Geometry · Mathematics 2007-05-23 Rares Rasdeaconu

Simple finite dimensional Kantor triple systems over the complex numbers are classified in terms of Satake diagrams. We prove that every simple and linearly compact Kantor triple system has finite dimension and give an explicit presentation…

Quantum Algebra · Mathematics 2019-05-31 Nicoletta Cantarini , Antonio Ricciardo , Andrea Santi

Based on projective representations of smooth Deligne cohomology groups, we introduce an analogue of the space of conformal blocks to compact oriented (4k+2)-dimensional Riemannian manifolds with boundary. For the standard…

Differential Geometry · Mathematics 2007-05-28 Kiyonori Gomi

We determine and classify all finite-dimensional Hopf algebras over an algebraically closed field of characteristic zero whose Hopf coradicals are isomorphic to dual Radford algebras of dimension $4p$ for a prime $p>5$. In particular, we…

Quantum Algebra · Mathematics 2022-09-27 Rongchuan Xiong , Naihong Hu

We prove a boundedness result for klt pairs $(X,B)$ such that $K_X+B\equiv 0$ and $B$ is big. As a consequence we obtain a positive answer to the Effective Iitaka Fibration Conjecture for klt pairs with big boundary.

Algebraic Geometry · Mathematics 2014-10-31 Christopher D. Hacon , Chenyang Xu

Let $(X/Z,B+A)$ be a $\Q$-factorial dlt pair where $B,A\ge 0$ are $\Q$-divisors and $K_X+B+A\sim_\Q 0/Z$. We prove that any LMMP$/Z$ on $K_X+B$ with scaling of an ample$/Z$ divisor terminates with a good log minimal model or a Mori fibre…

Algebraic Geometry · Mathematics 2012-04-25 Caucher Birkar

We prove that one can run the log minimal model program for log canonical $3$-fold pairs in characteristic $p>5$. In particular we prove the Cone Theorem, Contraction Theorem, the existence of flips and the existence of log minimal models…

Algebraic Geometry · Mathematics 2017-01-11 Joe Waldron

We reduce Iitaka's subadditivity conjecture for the logarithmic Kodaira dimension to a special case of the generalized abundance conjecture by establishing an Iitaka type inequality for Nakayama's numerical Kodaira dimension. Our proof…

Algebraic Geometry · Mathematics 2016-02-09 Osamu Fujino

The Kuperberg invariant is a topological invariant of closed 3-manifolds based on finite-dimensional Hopf algebras. In this paper, we initiate the program of constructing 4-manifold invariants in the spirit of Kuperberg's 3-manifold…

Quantum Algebra · Mathematics 2023-03-22 Julian Chaidez , Jordan Cotler , Shawn X. Cui

In this paper, we generalise the theory of complements to log canonical log fano varieties and prove boundedness of complements for them in dimension less than or equal to 3. We also prove some boundedness results for the canonical index of…

Algebraic Geometry · Mathematics 2019-01-15 Yanning Xu

Suppose that A and B are symplectomorphic smooth affine varieties. If A is acylic of dimension 2 then B has the same log Kodaira dimension as A. If the dimension of A is 3, has log Kodaira dimension 2 and satisfies some other conditions…

Symplectic Geometry · Mathematics 2012-11-12 Mark McLean

We show that the algebraic local fundamental group of any klt singularity as well as the algebraic fundamental group of the smooth locus of any log Fano variety are finite.

Algebraic Geometry · Mathematics 2019-02-20 Chenyang Xu

Let $(X,D)$ be a log smooth pair of dimension $n$, where $D$ is a reduced effective divisor such that the log canonical divisor $K_X + D$ is pseudo-effective. Let $G$ be a connected algebraic subgroup of $\mathrm{Aut}(X,D)$. We show that…

Algebraic Geometry · Mathematics 2019-07-08 Fei Hu

We discuss the behavior of the Kodaira dimension under smooth morphisms.

Algebraic Geometry · Mathematics 2024-07-15 Osamu Fujino , Taro Fujisawa

In this paper, we prove that the zero-locus of any global holomorphic log-one-form on a projective log-smooth pair $\left(X,D\right)$ of log-general type must be non-empty. Applying this result, we give an answer to the algebraic…

Algebraic Geometry · Mathematics 2017-11-17 Chuanhao Wei

We prove the following results for projective klt pairs of dimension $3$ over an algebraically closed field of char $p>5$: the cone theorem, the base point free theorem, the contraction theorem, finiteness of minimal models, termination…

Algebraic Geometry · Mathematics 2014-10-17 Caucher Birkar , Joe Waldron

We study the behavior of the Kodaira dimension of algebraic fiber spaces over threefolds. We prove some cases of the Iitaka Conjecture $C_{n,3}$, including certain situations where the base variety is a Calabi--Yau threefold.

Algebraic Geometry · Mathematics 2026-05-12 Houari Benammar Ammar

We show that every two-parameter period map admits a Kato--Nakayama--Usui completion to a morphism of log manifolds.

Algebraic Geometry · Mathematics 2023-12-04 Haohua Deng , Colleen Robles