AGT - Artículos
Envíos recientes
-
Homemade algebraic geometry: celebrating Enrique Arrondo’s 60th birthday
(Springer, 2024)In this survey we recognize Enrique Arrondo’s contributions over the whole of his career, recalling his professional history and collecting the results of his mathematical productio -
Smooth actions of connected compact Lie groups with a free point are determined by two vector fields
(Elsevier, 2024-04-10)Consider a smooth action of a compact connected Lie group G on a connected manifold M. Assume the existence of a point of M whose isotropy group has a single element (a free point). Then we prove that there exist two ... -
The Achievement Set of Generalized Multigeometric Sequences
(Springer, 2024-04-13)We study the topology of all possible subsums of the generalized multigeometric series where are fixed positive real numbers and f runs along a certain class of non-negative functions on the unit interval. We detect ... -
On isomorphism conditions for algebra functors with applications to Leavitt Path Algebras
(SpringerLink, 2023-07)We introduce certain functors from the category of commu- tative rings (and related categories) to that of Z-algebras (not neces- sarily associative or commutative). One of the motivating examples is the Leavitt path ... -
Tensor product of evolution algebras.
(SpringerLink, 2022-12-28)The starting point of this work is the fact that the class of evolution algebras over a fixed field is closed under tensor product. We prove that, under certain conditions, the tensor product is an evolution algebra if and ... -
Two-dimensional perfect evolution algebras over domains
(SpringerLink, 2023-01)We will study evolution algebras A that are free modules of dimension two over domains. We start by making some general considerations about algebras over domains: They are sandwiched between a certain essential D-submodule ... -
Ternary mappings of triangular algebras
(SpringerLink, Aequationes Mathematicae, 2021-03)We take acategorical approach to describe ternary derivations and ternary automorphisms of triangular algebras. New classes of automorphisms and derivations of triangular algebras are also introduced and studied. -
Classification of leavitt path algebras with two vertices
(Independent University of Moscow, 2019-07)We classify row-finite Leavitt path algebras associated to graphs with no more than two vertices. For the discussion we use the following invariants: decomposability, the K0 group, detpNE1 q (included in the Franks ... -
Using the Steinberg Algebra Model to determine the center of any Leavitt Path Algebra
(Springer, 2019-04)Given an arbitrary graph, we describe the center of its Leavitt path algebra over a commutative unital ring. Our proof uses the Steinberg algebra model of the Leavitt path algebra. A key ingredient is a characterization ... -
Squares and associative representations of two dimensional evolution algebras
(World Scientific, 2021)We associate an square to any two dimensional evolution algebra. This geomet- ric object is uniquely determined, does not depend on the basis and describes the structure and the behaviour of the algebra. We determine the ... -
Invariant ideals in Leavitt path algebras.
(Universitat Autònoma de Barcelona, Departament de Matemàtiques. Revista: Publications Matematiques, 2020-06-23)It is known that the ideals of a Leavitt path algebra LK (E) generated by Pl(E), by Pc(E) or by Pec(E) are invariant under isomorphism. Though the ideal generated by Pb∞ (E) is not invariant we find its “natural” replacement ... -
Decompositions of endomorphisms into a sum of roots of the unity and nilpotent endomorphisms of fixed nilpotence.
(Elsevier, 2023-07-10)For n ≥ 2 and fixed k ≥ 1, we study when an endomorphism f of Fn, where F is an arbitrary field, can be decomposed as t + m where t is a root of the unity endomorphism and m is a nilpotent endomorphism with mk = 0. For ... -
Gradings induced by nilpotent elements.
(Elsevier, 2023)An element a is nilpotent last-regular if it is nilpotent and its last nonzero power is von Neumann regular. In this paper we show that any nilpotent last-regular element a in an associative algebra R over a ring of scalars ... -
A filtration associated to an abelian inner ideal of a Lie algebra.
(Elsevier, 2022-12-14)Let B be an abelian inner ideal and let KerL B be the kernel of B. In this paper we show that when there exists n ∈ N with [B,KerL B] n ⊂ B, the inner ideal B induces a bounded filtration in L where B is the first nonzero ... -
Decompositions of matrices into a sum of invertible matrices and matrices of fixed nilpotence.
(International Linear Algebra Society, 2023-08-24)For any n ≥ 2 and fixed k ≥ 1, we give necessary and sufficient conditions for an arbitrary nonzero square matrix in the matrix ring Mn(F) to be written as a sum of an invertible matrix U and a nilpotent matrix N with Nk ... -
Tensor Product of Evolution Algebras
(Springer Nature, 2022-12-28)The starting point of this work is the fact that the class of evolution algebras over a fixed field is closed under tensor product. We prove that, under certain conditions, the tensor product is an evolution algebra if and ... -
Two-dimensional perfect evolution algebras over domains.
(Springer Nature, 2023-01-23)We will study evolution algebras A that are free modules of dimension two over domains. We start by making some general considerations about algebras over domains: They are sandwiched between a certain essential D-submodule ... -
Groups as automorphisms of dessins d’enfants
(Springer, 2022-08-01)It is known that every finite group can be represented as the full group of automorphisms of a suitable compact dessin d’enfant. In this paper, we give a constructive and easy proof that the same holds for any countable ... -
Classification of fiber sequences with a prescribed holonomy action
(Elsevier, 2022-08-01)We define H-fibration sequences as fibrations where the holonomy action of the fundamental group of the base on the fiber lies in a given subgroup H of E(F ), where E(F ) is the homotopy automorphism group of the fiber. ... -
Contact structures on null hypersurfaces
(Elsevier, 2022-08)The aim of this paper is to show how we can induce contact structures, contact metric structures and Sasaki structures on a null hypersurface from a rigging vector field. We give several explicit examples of this construction ...