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We prove a finiteness result for dominant rational maps whose orbifold base is of general type. Our finiteness result generalizes Maehara's theorem that a given variety dominates only finitely many projective varieties of general type up to…

Algebraic Geometry · Mathematics 2026-04-01 Finn Bartsch , Ariyan Javanpeykar , Erwan Rousseau

We provide a purely combinatorial proof of a skein exact sequence obeyed by double-point enhanced grid homology. We also extend the theory to coefficients over $\mathbb{Z},$ and discuss alternatives to the Ozsv\'ath-Szab\'o $\tau$…

Geometric Topology · Mathematics 2025-02-19 Ollie Thakar

Let $V\subset\R^m$ be a centrally symmetric convex body and let $V^*\subset\R^m$ be its polar. We prove limit relations between the sharp constants in the multivariate Markov-Bernstein-Nikolskii type inequalities for algebraic polynomials…

Classical Analysis and ODEs · Mathematics 2020-02-27 Michael I. Ganzburg

The inverse eigenvalue problem of a graph studies the real symmetric matrices whose off-diagonal pattern is prescribed by the adjacencies of the graph. The strong spectral property (SSP) is an important tool for this problem. This note…

Combinatorics · Mathematics 2022-04-19 Shaun M. Fallat , H. Tracy Hall , Jephian C. -H. Lin , Bryan L. Shader

Claude Chevalley provided a basis for a {finite dimensional} simple complex Lie algebra called the Chevalley basis. This basis has the distinguishing property that all the structure constants are integers. Chevalley groups, which are…

Quantum Algebra · Mathematics 2025-09-09 Saeid Azam

A different proof to a known criterion of derived equivalence implying birationality is given. Derived equivalent smooth projective curves over an algebraically closed field are proved to be isomorphic. A different proof of derived…

Algebraic Geometry · Mathematics 2011-08-10 Yu-Han Liu

In this paper we first introduce the unified definition of the sharp constant that includes constants in three major problems of approximation theory, such as, inequalities for approximating elements, approximation of individual elements,…

Classical Analysis and ODEs · Mathematics 2022-12-26 Michael I. Ganzburg

This is a survey on the finite basis problem for varieties of algebraic systems. Our exposition is in two directions: (i) We give numerous examples of varieties which are not finitely based. (ii) We give examples of important varieties with…

Rings and Algebras · Mathematics 2026-02-24 Vesselin Drensky

Schmidt's subspace theorem in terms of Seshadri constants for closed subschemes in subgeneral position has been already developed sharply. We derive our theorem for numerically equivalent ample divisors by dint of the above theory step by…

Number Theory · Mathematics 2025-06-16 GuanHeng Zhao

A multivariate Gauss-Lucas theorem is proved, sharpening and generalizing previous results on this topic. The theorem is stated in terms of a seemingly new notion of convexity. Applications to multivariate stable polynomials are given.

Complex Variables · Mathematics 2012-03-30 Marek Kanter

In this paper we explore the link between the theory of sheaves on graphs and noncommutative geometry showing that many concepts and constructions in the latter can be generalized and enhanced using methods coming from the former. They…

Differential Geometry · Mathematics 2026-02-25 Rita Fioresi , Angelica Simonetti , Ferdinando Zanchetta

We define a general notion of centrally $\Gamma$-graded sets and groups and of their graded products, and prove some basic results about the corresponding categories: most importantly, they form braided monoidal categories. Here, $\Gamma$…

Category Theory · Mathematics 2021-09-03 Wolfgang Bertram

A theory of graded manifolds can be viewed as a generalization of differential geometry of smooth manifolds. It allows one to work with functions which locally depend not only on ordinary real variables, but also on $\mathbb{Z}$-graded…

Differential Geometry · Mathematics 2023-03-14 Jan Vysoky

Using the notion of existentially closed structures, we obtain embedding theorems for groups and Lie algebras. We also prove the existence of some groups and Lie algebras with prescribed properties.

Group Theory · Mathematics 2014-05-07 M. Shahryari

We prove variational forms of the Barban-Davenport-Halberstam Theorem and the large sieve inequality. We apply our result to prove an estimate for the sum of the squares of prime differences, averaged over arithmetic progressions.

Number Theory · Mathematics 2012-02-07 Allison Lewko , Mark Lewko

We analyze families of non-autonomous systems of first-order ordinary differential equations admitting a common time-dependent superposition rule, i.e., a time-dependent map expressing any solution of each of these systems in terms of a…

Classical Analysis and ODEs · Mathematics 2011-11-22 Jose F. Carinena , Janusz Grabowski , Javier de Lucas

We prove the two theorems of the title, settling two long standing questions in the local theory of singular minimal hypersurfaces. The sharpness of either result is with respect to its hypothesis on the size of the allowable singular sets.…

Differential Geometry · Mathematics 2013-10-16 Neshan Wickramasekera

We instal homological algebra, including derived functors, on certain non-additive categories like categories of pointed CW-complexes, modules of monoids or sheaves thereof. We apply this theory to Monoid schemes and sheaves on them,…

Number Theory · Mathematics 2017-09-04 Anton Deitmar

In this work, we present a generalization of Gale's lemma. Using this generalization, we introduce two combinatorial sharp lower bounds for ${\rm conid}({\rm B}_0(G))+1$ and ${\rm conid}({\rm B}(G))+2$, two famous topological lower bounds…

Combinatorics · Mathematics 2016-08-01 Meysam Alishahi , Hossein Hajiabolhassan

In this note, we provide several constructions of Deza Cayley graphs over groups having a generalized dihedral subgroup. These constructions are based on a usage of (relative) difference sets.

Combinatorics · Mathematics 2026-01-15 Grigory Ryabov