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Natalia A. Viana Bedoya

Publications and source records attributed to Natalia A. Viana Bedoya.

7 recordsLinked to original sources
arXiv2025

Group actions and automorphisms of evolution algebras associated to finite graphs

Given an evolution algebra associated to a connected finite graph $Γ$, we exhibit a free action of the group of symmetries of $Γ$ on the set of automorphisms of the algebra. This allows us to explicitly describe this set and we prove that a sufficient condition for it to be finite is that every automorphism is induced by a graph symmetry. Consequently, we extend a known result about perfect evolution algebras to other families.

math.RA↗
arXiv2025

A group from a map and orbit equivalence

In two papers published in 1979, R. Bowen and C. Series defined a dynamical system from a Fuchsian group, acting on the hyperbolic plane $\mathbb{H}^2$. The dynamics is given by a map on $S^1$ which is, in particular, an expanding piecewise homeomorphism of the circle. In this paper we consider a reverse question: which dynamical conditions for an expanding piecewise homeomorphism of $S^1$ are sufficient for the map to be a ``Bowen-Series-type" map (see below) for some group $G$ and which groups can occur? We give a partial answer to these questions.

math.DS↗
arXiv2023

Decomposability of minimal defect branched coverings over the projective plane

In this paper we characterize primitive branched coverings with minimal defect over the projective plane with respect to the properties decomposable and indecomposable. This minimality is achieved when the covering surface is also the projective plane, which corresponds to the last case to be solved. As a consequence, we have extended the family of realisations of branched coverings on the projective plane and established a type of generalisation of results on primitive permutation groups.

math.GT↗
arXiv2022

Geometrization of Piecewise homeomorphisms of the circle

In this work we study the following realization problem: given a piecewise homeomorphism $Φ: S^1 \rightarrow S^1$, which geometrical and dynamical conditions on $Φ$ are sufficient to realize it as a Bowen-Series-like map associated to a surface group, seen as a discrete subgroup of ${\rm Homeo}^+ (S^1)$?

math.DS↗
arXiv2017

Indecomposable branched coverings over the projective plane by surfaces $M$ with $χ(M) \leq 0$

In this work we study the decomposability property of branched coverings of degree $d$ odd, over the projective plane, where the covering surface has Euler characteristic $\leq 0$. The latter condition is equivalent to say that the defect of the covering is greater than $d$. We show that, given a datum $\mathscr{D}=\{D_{1},\dots,D_{s}\}$ with an even defect greater than $d$, it is realizable by an indecomposable branched covering over the projective plane. The case when $d$ is even is known.

math.GT↗
arXiv2010

Decomposability problem on branched coverings

Given a branched covering of degree d between closed surfaces, it determines a collection of partitions of d, the branch data. In this work we show that any branch data are realized by an indecomposable primitive branched covering on a connected close surface N with Euler's characteristic less than or equal to 0. This shows that decomposable and indecomposable realizations may coexist. Moreover, we characterize the branch data of a decomposable primitive branched covering.

math.GT↗