arXiv subjects

Jesús Alonso Ochoa Arango

Publications and source records attributed to Jesús Alonso Ochoa Arango.

4 recordsLinked to original sources

arXiv2024

On the number of exact factorization of finite Groups

In this work, we study the function $f_2(G)$ that counts the number of exact factorizations of a finite group $G$. We compute $f_2(G)$ for some well-known families of finite groups and use the results of Wiegold and Williamson \cite{WW} to derive an asymptotic expression for the number of exact factorizations of the alternating group $A_{2^n}$. Finally, we propose several questions about the function $f_2(G)$ that may be of interest for further research.

math.GR↗

arXiv2024

On an uncertainty principle for small index subgroups of finite fields

In this paper we continue the study of the nonvanishing minors property (NVM) initiated by Garcia, Karaali and Katz, for the compressed Fourier matrix attached to a subgroup $H$ of the multiplicative group of a finite field $\mathbb{F}_q$ and a character $χ$ defined over $H$. Here we provide a characterization of this aforementioned property for \textit{symmetries} arising from an index-3 subgroup $H$ and a nontrivial character $χ$.

math.NT↗

arXiv2018

The Automorphisms group of a Current Lie algebra

Let $\mathfrak{g}$ be a finite dimensional complex Lie algebra and let $A$ be a finite dimensional complex, associative and commutative algebra with unit. We describe the structure of the derivation Lie algebra of the current Lie algebra $\mathfrak{g}_A= \mathfrak{g} \otimes A$, denoted by $\operatorname{Der}(\mathfrak{g}_A)$. Furthermore, we obtain the Levi decomposition of $\operatorname{Der}(\mathfrak{g}_A)$. As a consequence of the last result, if $\mathfrak{h}_m$ is the Heisenberg Lie algebra of dimension $2 m + 1$, we obtain a faithful representation of $\operatorname{Der}(\mathfrak{h}_{m,k})$ of the current truncated Heisenberg Lie algebra $\mathfrak{h}_{m,k}= \mathfrak{h}_m \otimes \mathbb{C}[t]/ (t^{k + 1})$ for all positive integer $k$.

math.RT↗

arXiv2016

Double groupoid cohomology and extensions

We study extensions of double groupoids in the sense of \cite{AN2} and show some classical results of group theory extensions in the case of double groupoids. For it, given a double groupoid $(\mathcal{B}; \mathcal{V},\mathcal{H}; \mathcal{P})$ \emph{acting} on an abelian group bundle $\mathbf{K} \to \mathcal{P}$, we introduce a cohomology double complex, in a similar way as was done in \cite{AN2} and we show that the extensions of $\mathcal{F}$ by $\mathbf{K}$ are classified by the total first cohomology group of the associated total complex. With the aim to extend the above results to the topological setting, following ideas of Deligne \cite{D} and Tu \cite{tu}, by means of simplicial methods, we introduce a \emph{sheaf cohomology} for topological double groupoids, generalizing the double groupoid cohomological in the discrete case, and we carry out in the topological setting the results obtained for discrete double groupoids.

math.KT↗