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For an arbitrary separated scheme $X$ of finite type over a finite field $\mathbb F_q$ and an integer $j=-1,-2,$ we prove under the assumption of resolution of singularities, that the two groups $H_{-1}(X,\mathbb Z(j))$ and…

K-Theory and Homology · Mathematics 2017-06-14 Tohru Kohrita

Theoretical foundations of a new algorithm for determining the p-capitulation type kappa(K) of a number field K with p-class rank rho=2 are presented. Since kappa(K) alone is insufficient for identifying the second p-class group…

Number Theory · Mathematics 2016-05-13 Daniel C. Mayer

We prove that if there are $\mathfrak c$ incomparable selective ultrafilters then, for every infinite cardinal $\kappa$ such that $\kappa^\omega=\kappa$, there exists a group topology on the free Abelian group of cardinality $\kappa$…

Logic · Mathematics 2021-03-25 M. K. Bellini , K. P. Hart , V. O. Rodrigues , A. H. Tomita

Character groups of Hopf algebras appear in a variety of mathematical contexts such as non-commutative geometry, renormalisation of quantum field theory, numerical analysis and the theory of regularity structures for stochastic partial…

Group Theory · Mathematics 2019-02-14 Geir Bogfjellmo , Alexander Schmeding

In the hyperalgebra of the $r$-th Frobenius kernel of a universal Chevalley group over a field of characteristic $p>0$, we study some subsets and the subalgebras generated by them and give some results. We are particularly interested in the…

Rings and Algebras · Mathematics 2023-11-14 Yutaka Yoshii

Let $G$ be a finite group and $\pi$ be a set of primes. We study finite groups with a large number of conjugacy classes of $\pi$-elements. In particular, we obtain precise lower bounds for this number in terms of the $\pi$-part of the order…

Group Theory · Mathematics 2023-05-31 N. N. Hung , A. Maróti , J. Martínez

We present new computational results for symplectic monodromy groups of hypergeometric differential equations. In particular, we compute the arithmetic closure of each group, sometimes justifying arithmeticity. The results are obtained by…

Group Theory · Mathematics 2020-06-09 A. S. Detinko , D. L. Flannery , A. Hulpke

The quantum Galilei group $G_{\varkappa}$ is defined. The bicrossproduct structure of $G_{\varkappa}$ and the corresponding Lie algebra is revealed. The projective representations for the two-dimensional quantum Galilei group are…

q-alg · Mathematics 2009-10-28 S. Giller , C. Gonera , P. Kosiński , P. Maślanka

Let $(X,\Delta)$ be a pair. We study how the condition $\kappa(K_X + \Delta)=0$ causes surjectivity or birationality of the Albanese map and the Albanese morphism of $X$ in both characteristic $0$ and characteristic $p > 0$. In particular…

Algebraic Geometry · Mathematics 2018-01-23 Yuan Wang

In this paper we identify many striking elements in Leibniz (co)homology which arise from characteristic classes and K-theory. For a group G a field k of characteristic zero, it is shown that all primary characteristic classes, i.e. H^*(BG;…

K-Theory and Homology · Mathematics 2007-05-23 Jerry Lodder

Let $V$ be a finite-dimensional unitary representation of a compact quantum group $\mathrm{G}$ and denote by $\mathrm{G}_W$ the isotropy subgroup of a linear subspace $W\le V$ regarded as a point in the Grassmannian $\mathbb{G}(V)$. We show…

Quantum Algebra · Mathematics 2025-05-13 Alexandru Chirvasitu

In this article, we address the classification of smooth projective algebraic surfaces over complex numbers admitting algebraic semigroup structures. We give a full description of those surfaces $S$, which has at least one non-trivial…

Algebraic Geometry · Mathematics 2015-09-10 Duo Li

We study the relation between the structure of algebraic and context-free subsets of a group G and that of a finite index subgroup H. Using these results, we prove that a kind of Fatou property, previously studied by Berstel and Sakarovitch…

Group Theory · Mathematics 2023-10-16 André Carvalho

The Zariski theorem says that for every hypersurface in a complex projective (resp. affine) space of dimension at least 3 and for every generic plane in the projective (resp. affine) space the natural embedding generates an isomorphism of…

alg-geom · Mathematics 2007-05-23 Shulim Kaliman

A perfect code in a graph $\Gamma = (V, E)$ is a subset $C$ of $V$ such that no two vertices in $C$ are adjacent and every vertex in $V \setminus C$ is adjacent to exactly one vertex in $C$. A subgroup $H$ of a group $G$ is called a…

Combinatorics · Mathematics 2026-05-06 Binbin Li , Jingjian Li , Wei Meng , Hao Yu

A morphism of linear algebraic groups $\phi:K\rightarrow G$ is called an epimorphism if it admits right cancellation. A subgroup $H\leq G$ is epimorphic if the inclusion map is an epimorphism. For $G$ a simple algebraic group over an…

Group Theory · Mathematics 2025-05-05 Donna M. Testerman , Adam R. Thomas

In this paper we study generalizations of classical results on intersection patterns of set systems in $\mathbb{R}^d$, such as the fractional Helly theorem or the $(p,q)$-theorem, in the setting of arbitrary triangulable spaces with a…

Computational Geometry · Computer Science 2026-05-19 Xavier Goaoc , Andreas F. Holmsen , Zuzana Patáková

The objective of this paper is to describe the structure of Zariski closed algebras, which provide a useful generalization to finite dimensional algebras in the study of representable algebras over finite fields. Our results include a…

Rings and Algebras · Mathematics 2011-09-23 Alexei Belov-Kanel , Louis H. Rowen , Uzi Vishne

Let $\mathbf{P}$ be a parabolic subgroup with Levi $\mathbf{M}$ of a connected reductive group defined over a locally compact non-archimedean field $F$. Given a certain compact open subgroup $\Gamma$ of $\mathbf{P}(F)$, this note proves…

Representation Theory · Mathematics 2021-04-01 Claudius Heyer

We investigate the class of FHP theories, i.e. theories of structures in which all definable families of sets satisfy the Fractional Helly Property (and its variants) from combinatorics. FHP theories generalize NIP and form a new subclass…

Logic · Mathematics 2026-05-19 Artem Chernikov , Chuyin Jiang