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Related papers: Effective non-vanishing and Mukai type conjecture

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In our previous work we conjectured - inspired by an algebro-geometric result of Fujita - that the height of an arithmetic Fano variety X of relative dimension $n$ is maximal when X is the projective space $\mathbb{P}^n_{\mathbb{Z}}$ over…

Algebraic Geometry · Mathematics 2024-03-05 Rolf Andreasson , Robert J. Berman

We construct klt projective varieties with ample canonical class and the smallest known volume. We also find exceptional klt Fano varieties with the smallest known anticanonical volume. We conjecture that our examples have the smallest…

Algebraic Geometry · Mathematics 2022-11-03 Burt Totaro

We initiate a systematic quantitative study of subsets of rational points that are integral with respect to a weighted boundary divisor on Fano orbifolds. We call the points in these sets Campana points. Earlier work of Campana and…

Number Theory · Mathematics 2020-11-18 Marta Pieropan , Arne Smeets , Sho Tanimoto , Anthony Várilly-Alvarado

We prove a Kodaira-type vanishing theorem for the Witt vector sheaf on a Fano variety over a perfect field of characteristic p. As a corollary, we deduce that the number of rational points on a Fano variety over a finite field with q=p^n…

Algebraic Geometry · Mathematics 2007-05-23 Minhyong Kim

By applying the Chen-Jiang decomposition, we prove that the non-vanishing conjecture holds for an lc pair \((X, \Delta)\), where \(X\) is an irregular variety, provided it holds for lower-dimensional varieties. In the second part, we extend…

Algebraic Geometry · Mathematics 2025-01-09 Houari Benammar Ammar

In a recent preprint, Y. Namikawa proposed a conjecture on Q-factorial terminalizations and their birational geometry of nilpotent orbits. He proved his conjecture for classical simple Lie algebras. In this note, we prove his conjecture for…

Algebraic Geometry · Mathematics 2020-08-19 Baohua Fu

In this paper, we prove the existence portion of the Bertram-Feinberg-Mukai Conjecture for an infinite family of new cases using degeneration technique. This not only leads to a substantial improvement of known results but also develops…

Algebraic Geometry · Mathematics 2016-08-29 Naizhen Zhang

Let $F$ be a totally real field and $K$ a finite abelian CM extension of $F$. Using class field theory, we show that our previous result giving a strong form of the Brumer-Stark conjecture implies the minus part of the equivariant Tamagawa…

Number Theory · Mathematics 2023-12-18 Samit Dasgupta , Mahesh Kakde , Jesse Silliman

We propose an analogue of Dubrovin's conjecture for the case where Fano manifolds have quantum connections of exponential type. It includes the case where the quantum cohomology rings are not necessarily semisimple. The conjecture is…

Algebraic Geometry · Mathematics 2021-01-18 Fumihiko Sanda , Yota Shamoto

We establish an algebraic approach to prove the properness of moduli spaces of K-polystable Fano varieties and reduce the problem to a conjecture on destabilizations of K-unstable Fano varieties. Specifically, we prove that if the stability…

Algebraic Geometry · Mathematics 2021-07-20 Harold Blum , Daniel Halpern-Leistner , Yuchen Liu , Chenyang Xu

We prove effective forms of the Sato-Tate conjecture for holomorphic cuspidal newforms which improve on the author's previous work (solo and joint with Lemke Oliver). We also prove an effective form of the joint Sato-Tate distribution for…

Number Theory · Mathematics 2021-03-11 Jesse Thorner

Given any field $k$ (not necessarily perfect), we study the smoothing of a semistable Fano variety over $k$. In characteristic 0, the reduced semistable Fano degenerate fibers of Mori fibrations are classified. In positive characteristic,…

Algebraic Geometry · Mathematics 2016-06-03 Junchao Shentu

We give a survey on noncommutative main conjectures of Iwasawa theory in a geometric setting, i.e. for separated schemes of finite type over a finite field, as stated and proved by Burns and the author. We will also comment briefly on…

Number Theory · Mathematics 2012-05-15 Malte Witte

In this note, we shall prove that two smooth projective varieties of dim 2n connected by a Mukai flop have equivalent bounded derived categories. More precisely, let $\phi : X - - \to X^+$ be a Mukai flop with centers $Y \subset X$ and $Y^+…

Algebraic Geometry · Mathematics 2007-05-23 Yoshinori Namikawa

The symmetric projective varieties of rank one are all smooth and Fano by a classic result of Akhiezer. We classify the locally factorial (respectively smooth) projective symmetric $G$-varieties of rank 2 which are Fano. When $G$ is…

Algebraic Geometry · Mathematics 2010-12-22 Alessandro Ruzzi

Geometric Manin's conjecture predicts that components of the moduli space of curves on a Fano variety parametrizing non-free curves are pathological and arise from "accumulating" morphisms that increase the Fujita invariant. By passing to…

Algebraic Geometry · Mathematics 2026-02-10 Matthew Hase-Liu

We construct exceptional Fano varieties with the smallest known minimal log discrepancies in all dimensions. These varieties are well-formed hypersurfaces in weighted projective space. Their minimal log discrepancies decay doubly…

Algebraic Geometry · Mathematics 2024-06-07 Louis Esser , Jihao Liu , Chengxi Wang

We prove a generating function formula for the Betti numbers of Nakajima quiver varieties. We prove that it is a q-deformation of the Weyl-Kac character formula. In particular this implies that the constant term of the polynomial counting…

Representation Theory · Mathematics 2010-03-17 Tamas Hausel

We prove that the non-vanishing conjecture and the log minimal model conjecture for projective log canonical pairs can be reduced to the non-vanishing conjecture for smooth projective varieties such that the boundary divisor is zero.

Algebraic Geometry · Mathematics 2017-11-22 Kenta Hashizume

We describe the irreducible components of the moduli spaces of rational curves on Artin-Mumford double solids. This provides the first example of Fano varieties that satisfy Geometric Manin's Conjecture with multiple Manin components in…

Algebraic Geometry · Mathematics 2025-01-17 Fumiya Okamura