English
Related papers

Related papers: Moving Seshadri constants and effective Fujita-typ…

200 papers

This work consists of two parts. In the first part we develop new techniques to compute Koszul cohomology groups for several classes of varieties. As applications we prove results on projective normality and syzygies for algebraic surfaces.…

alg-geom · Mathematics 2008-02-03 F. J. Gallego , B. P. Purnaprajna

We propose a new class of filtered vector bundles, which is related to variation of (mixed) Hodge structures and give a slight generalization of the Fujita--Zucker--Kawamata semipositivity theorem.

Algebraic Geometry · Mathematics 2017-10-10 Taro Fujisawa

In this article we compute Seshadri constants of ample line bundles on the blowup of Hirzebruch surface $\mathbb{F}_e$ at $r\leqslant e+3$ very general points. Similarly, we compute Seshadri constants on the blowups of certain decomposable…

Algebraic Geometry · Mathematics 2025-01-10 Cyril J. Jacob , Bivas Khan , Ronnie Sebastian

It is shown that the weak multidimensional Suita conjecture fails for any bounded non-pseudoconvex domain with $C^{1+\varepsilon_-}$-smooth boundary. On the other hand, it is proved that the weak converse to the Suita conjecture holds for…

Complex Variables · Mathematics 2018-08-14 Nikolai Nikolov

In this paper we develop a theory of curvature (resp. multiplicity) invariant for tensor products of full Fock spaces and also for tensor products of symmetric Fock spaces. This is an attempt to find a more general framework for these…

Functional Analysis · Mathematics 2015-03-16 Gelu Popescu

Motivated by work of Zhang from the early `90s, Medvedev and Scanlon formulated the following conjecture. Let $K$ be an algebraically closed field of characteristic $0$ and let $X$ be a quasiprojective variety defined over $K$ endowed with…

Algebraic Geometry · Mathematics 2016-10-24 Jason P. Bell , Dragos Ghioca , Zinovy Reichstein , Matthew Satriano

In this paper, we study rational sections of the relative Picard variety of a linear system on a smooth projective variety. Specifically, we prove that if the linear system is basepoint-free and the locus of non-integral divisors has…

Algebraic Geometry · Mathematics 2014-02-11 Matthew Woolf

We prove the following generalization of Severi's Theorem: Let $X$ be a fixed complex variety. Then there exist, up to birational equivalence, only finitely many complex varieties $Y$ of general type of dimension at most three which admit a…

alg-geom · Mathematics 2014-12-02 Gerd Dethloff

In [7], Higashitani, Kummer, and Micha{\l}ek pose a conjecture about the symmetric edge polytopes of complete multipartite graphs and confirm it for a number of families in the bipartite case. We confirm that conjecture for a number of new…

Combinatorics · Mathematics 2024-04-03 Max Kölbl

We prove several results on the additivity of Kodaira dimension under smooth morphisms of smooth projective varieties.

Algebraic Geometry · Mathematics 2024-11-27 Mihnea Popa , Christian Schnell

Given a closed subscheme $Z$ of a polarized abelian variety $(A,\ell)$ we define its vanishing threshold with respect to $\ell$ and relate it to the Seshadri constant of the ideal defining $Z.$ As a particular case, we introduce the notion…

Algebraic Geometry · Mathematics 2025-05-12 Nelson Alvarado

We review the evidence behind recent claims of spatial variation in the fine structure constant deriving from observations of ionic absorption lines in the light from distant quasars. To this end we expand upon previous non-Bayesian…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-12 Ewan Cameron , Tony Pettitt

We consider an extended theory of Horava-Lifshitz gravity with the detailed balance condition softly breaking, but without the projectability condition. With the former, the number of independent coupling constants is significantly reduced.…

High Energy Physics - Theory · Physics 2012-03-01 Tao Zhu , Fu-Wen Shu , Qiang Wu , Anzhong Wang

We show that the $\ell$-adic Tate conjecture for divisors on smooth proper varieties over finitely generated fields of positive characteristic follows from the $\ell$-adic Tate conjecture for divisors on smooth projective surfaces over…

Algebraic Geometry · Mathematics 2021-05-11 Emiliano Ambrosi

Chow's Theorem and GAGA are renowned results demonstrating the algebraic nature of projective manifolds and, more broadly, projective analytic varieties. However, determining if a particular manifold is projective is not, generally, a…

Algebraic Geometry · Mathematics 2025-01-14 Skyler Marks

We formulate a conjecture characterizing smooth projective varieties in positive characteristic whose Frobenius morphism can be lifted modulo $p^2$ - we expect that such varieties, after a finite \'etale cover, admit a toric fibration over…

Algebraic Geometry · Mathematics 2021-02-08 Piotr Achinger , Jakub Witaszek , Maciej Zdanowicz

We study $l$-very ample, ample and semi-ample divisors on the blown-up projective space $\mathbb{P}^n$ in a collection of points in general position. We establish Fujita's conjectures for all ample divisors with the number of points bounded…

Algebraic Geometry · Mathematics 2017-09-18 Olivia Dumitrescu , Elisa Postinghel

We prove an analogue of the Hitchin-Kobayashi correspondence for compact, oriented, taut Riemannian foliated manifolds with transverse Hermitian structure. In particular, our Hitchin-Kobayashi theorem holds on any compact Sasakian manifold.…

Differential Geometry · Mathematics 2022-09-30 David Baraglia , Pedram Hekmati

Even though Zaremba's conjecture remains open, Bourgain and Kontorovich solved the problem for a full density subset. Nevertheless, there are only a handful of explicit sequences known to satisfy the strong version of the conjecture, all of…

Number Theory · Mathematics 2026-01-28 Elias Dubno

We generalize the result of Kawamata concerning the strong version of Fujita's freeness conjecture for smooth 3-folds to some singular cases, namely, Gorenstein terminal singularities and quotient singularities of type 1/r(1,1,1) and of…

Algebraic Geometry · Mathematics 2007-05-23 Nobuyuki Kakimi