International Conference “Classes of Groups, Algebras and their Applications” dedicated to the memory of Leonid A. Shemetkov, Gomel, Belarus, 3-6 July, 2014

Jul ’14Jul
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L. A. ShemetkovThe International Algebraic Conference “Classes of Groups, Algebras and their Applications”, dedicated to the memory of Corresponding Member of the National Academy of Sciences of Belarus, Honoured Scientist of Belarus, Doctor of Physical and Mathematical Sciences, Professor Leonid Alexandrovich Shemetkov will be held in Gomel on July 3-6, 2014.

http://agss-conf.org/shemetkov/

Deputy Chairman of the Organizing Committee M.V. Sel’kin

Program Committee Chairman A.N. Skiba

Executive Secretary V.A. Kovaleva

Adolfo Ballester-Bolinches and Ramón Esteban-Romero belong to the programme committee.

Charla de Ramón Esteban «Cómo usar las matemáticas para comunicarnos» martes 11/02 18.00 en La Nau Gran

Feb ’14
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18:00

El próximo martes 11 de febrero de 2014, a las 18.00, en la sala de actos «Charles Darwin» del aulario del campus de Burjassot, Ramón Esteban impartirá la charla titulada

«Cómo usar las matemáticas para comunicarnos»

como parte del 12º ciclo de conferencias «Temas de actualidad en Ciencias» de «La nau Gran», el programa universitario de la Universitat de València para mayores de 55 años. Estáis invitados a asistir.

Nota: Esta charla estaba prevista originalmente para el 8 de abril.

Resumen

En esta charla veremos algunos problemas que se pueden dar en el ámbito de la comunicación y cómo las matemáticas pueden ayudarnos a resolverlos. En concreto, uno de los problemas es el ruido puede producir errores en la transmisión de información que es necesario corregir o, al menos, detectar. Este es el objeto de la llamada teoría de códigos. Los dígitos o caracteres de control constituyen un mecanismo para mitigar el efecto de esos errores. La aritmética modular o aritmética del reloj nos permite diseñar sistemas de dígitos de control que nos sirven para detectar o corregir errores. Por otra parte, hay ocasiones en que interesa mantener en secreto alguna comunicación a salvo de terceras personas. Para ello, es necesario cifrarlo de modo que si alguien lo intercepta, no pueda entenderlo. De nuevo, la aritmética del reloj resulta ser una potente herramienta matemática que está en la base del diseño de muchos sistemas criptográficos. Durante la charla presentaremos las nociones básicas de la teoría de códigos y de la criptografía y mostraremos algunos ejemplos de dígitos de control y de sistemas criptográficos basados en la aritmética modular.

 

Paper “A description based on languages of the final non-deterministic automaton” accepted in Theoretical Computer Science

The paper “A description based on languages of the final non-deterministic automaton” has been accepted for publication in Theoretical Computer Science. The abstract can be found below. We will inform later about the publication details. It will be available on

http://dx.doi.org/10.1016/j.tcs.2014.01.018.

El artículo “A description based on languages of the final non-deterministic automaton” ha sido aceptado para su publicación en Theoretical Computer Science. El resumen aparece más abajo. Informaremos más adelante sobre los detalles bibliográficos. Estará disponible en

http://dx.doi.org/10.1016/j.tcs.2014.01.018.

L’article “A description based on languages of the final non-deterministic automaton” ha sigut acceptat per a la seua publicació en Theoretical Computer Science. El resum apareix davall. Informarem més endavant sobre els detalls bibliogràfics. Estarà disponible en

http://dx.doi.org/10.1016/j.tcs.2014.01.018.

Abstract: The study of the behaviour of non-deterministic automata has traditionally focused on the languages which can be associated to the different states. Under this interpretation, the different branches that can be taken at every step are ignored. However, we can also take into account the different decisions which can be made at every state, that is, the branches that can be taken, and these decisions might change the possible future behaviour. In this case, the behaviour of the automata can be described with the help of the concept of bisimilarity. This is the kind of description that is usually obtained when the automata are regarded as labelled transition systems or coalgebras.

Contrarily to what happens with deterministic automata, it is not possible to describe the behaviour up to bisimilarity of states of a non-deterministic automaton by considering just the languages associated to them. In this paper we present a description of a final object for the category of non-deterministic automata, regarded as labelled transition systems, with the help of some structures defined in terms of languages. As a consequence, we obtain a characterisation of bisimilarity of states of automata in terms of languages and a method to minimise non-deterministic automata with respect to bisimilarity of states. This
confirms that languages can be considered as the natural objects to describe the behaviour of automata.

Mathematics Subject Classification (2010): 68Q70, 68Q45, 68Q55, 18B20
Keywords: non-deterministic automaton, formal language, coalgebra, bisimilarity, final automaton.

Paper “On the p-length of some finite p-soluble groups” to appear in Israel J. Math.

The following paper has been accepted for publication. We will inform about the bibliographical details.

El siguiente artículo ha sido aceptado para su publicación. Informaremos sobre los detalles bibliográficos.

El següent article ha sigut acceptat per a la seua publicació. N’informarem sobre els detalls bibliogràfics.

A. Ballester-Bolinches, R. Esteban-Romero, Luis M. Ezquerro,

On the p-length of some finite p-soluble groups

Israel J. Math.

 

Abstract

The main aim of this paper is to give structural information of a finite group of minimal order belonging to a subgroup-closed class of finite groups and whose p-length is greater than 1, p a prime number. Alternative proofs and improvements of recent results about the influence of minimal p-subgroups on the p-nilpotence and p-length of a finite group arise as consequences of our study.

Paper “Algorithms for permutability in finite groups” published in Cent. Eur. J. Math.

The following paper has been published:

El siguiente artículo ha sido publicado:

El següent article ha sigut publicat:

A. Ballester-Bolinches, E. Cosme-Llópez, R. Esteban-Romero

Algorithms for permutability in finite groups

Cent. Eur. J. Math., 11 (11), 1914-1922 (2013).

Abstract: In this paper we describe some algorithms to identify permutable and Sylow-permutable subgroups of finite groups, Dedekind and Iwasawa finite groups, and finite T-groups (groups in which normality is transitive), PT-groups (groups in which permutability is transitive), and PST-groups (groups in which Sylow permutability is transitive). These algorithms have been implemented in a package for the computer algebra system GAP.

Keywords:  Finite group • Permutable subgroup • S-permutable subgroup • Dedekind group • Iwasawa group • T-group • PT-group • PST-group • Algorithm
Mathematics Subject Classification (2010):  20D10, 20D20, 20-04

http://dx.doi.org/10.2478/s11533-013-0299-4

 

Paper “Primitive subgroups and PST-groups” to appear in Bull. Aust. Math. Soc.

The following paper has been accepted for publication. We will inform about the publication details.

El siguiente artículo ha sido aceptado para su publicación. Informaremos sobre los detalles bibliográficos.

El següent article ha sigut acceptat per a la seua publicació. N’informarem sobre els detalls bibliogràfics.

A. Ballester-Bolinches, J. C. Beidleman, R. Esteban-Romero

Primitive groups and PST-groups

Bull. Aust. Math. Soc.

http://dx.doi.org/10.1017/S0004972713000592

Abstract

All groups considered in this paper are finite. A subgroup H of a group G is called a primitive subgroup if it is a proper subgroup in the intersection of all subgroups of G containing H as a proper subgroup. He et al. [‘A note on primitive subgroups of finite groups’, Commun. Korean Math. Soc. 28(1) (2013), 55–62] proved that every primitive subgroup of G has index a power of a prime if and only if G/Φ(G) is a solvable PST-group. Let X denote the class of groups G all of whose primitive subgroups have prime power index. It is established here that a group G is a solvable PST-group if and only if every subgroup of G is an X-group.

2010 Mathematics subject classification: primary 20D10; secondary 20D15, 20D20

Keywords and phrases: finite groups, primitive subgroups, solvable PST-groups, T0-groups

Paper “Graphs and classes of finite groups” published in Note Mat.

The following paper has been published.

El siguiente artículo ha sido publicado.

El següent article ha sigut publicat.

A. Ballester-Bolinches, John Cossey, R. Esteban-Romero

Graphs and classes of finite groups

Note Mat., 33 (1), 89-94 (2013)

http://dx.doi.org/10.1285/i15900932v33n1p89

Abstract. There are different ways to associate to a finite group a certain graph. An interesting question is to analyse the relations between the structure of the group, given in group-theoretical terms, and the structure of the graph, given in the language of graph theory. This survey paper presents some contributions to this research line.
Keywords: finite groups, classes of groups, graphs
MSC 2000 classification: primary 20D10, secondary 05C25

Publication data for “Maximal subgroups and PST-groups” in Cent. Eur. Math. J.

Central European Journal of MathematicsWe now have the issue and page numbers for the paper we mentioned in http://permut.blogs.uv.es/2013/03/15/paper-maximal-subgroups-and-pst-groups/.

Adolfo Ballester-Bolinches, James C. Beidleman, Ramón Esteban-Romero, Vicent Pérez-Calabuig

Maximal subgroups and PST-groups

Centr. Eur. J. Math., 11(6), 2013, 1078-1082,

available on http://dx.doi.org/10.2478/s11533-013-0222-z.

Abstract:

A subgroup H of a group G is said to permute with a subgroup K of G if HK is a subgroup of G. H is said to be permutable (resp. S-permutable) if it permutes with all the subgroups (resp. Sylow subgroups) of G. Finite groups in which permutability (resp. S-permutability) is a transitive relation are called PT-groups (resp. PST-groups). PT-, PST- and T-groups, or groups in which normality is transitive, have been extensively studied and characterised. Kaplan [Kaplan G., On T-groups, supersolvable groups, and maximal subgroups, Arch. Math. (Basel), 2011, 96(1), 19–25] presented some new characterisations of soluble T-groups. The main goal of this paper is to establish PT- and PST-versions of Kaplan’s results, which enables a better understanding of the relationships between these classes.

MSC:  20D05, 20D10, 20E15, 20E28, 20F16
Keywords: Finite groups • Permutability • Sylow-permutability • Maximal subgroups • Supersolubility

(c) Versita Sp. z. o. o. and Springer

 

Paper “Maximal subgroups and PST-groups” to appear in Cent. Eur. Math. J.

Central European Journal of MathematicsThe paper

Adolfo Ballester-Bolinches, James C. Beidleman, Ramón Esteban-Romero, Vicent Pérez-Calabuig

Maximal subgroups and PST-groups

Centr. Eur. J. Math., in press

is now available on http://dx.doi.org/10.2478/s11533-013-0222-z.

Abstract:

A subgroup H of a group G is said to permute with a subgroup K of G if HK is a subgroup of G. H is said to be permutable (resp. S-permutable) if it permutes with all the subgroups (resp. Sylow subgroups) of G. Finite groups in which permutability (resp. S-permutability) is a transitive relation are called PT-groups (resp. PST-groups). PT-, PST- and T-groups, or groups in which normality is transitive, have been extensively studied and characterised. Kaplan [Kaplan G., On T-groups, supersolvable groups, and maximal subgroups, Arch. Math. (Basel), 2011, 96(1), 19–25] presented some new characterisations of soluble T-groups. The main goal of this paper is to establish PT- and PST-versions of Kaplan’s results, which enables a better understanding of the relationships between these classes.

MSC:  20D05, 20D10, 20E15, 20E28, 20F16
Keywords: Finite groups • Permutability • Sylow-permutability • Maximal subgroups • Supersolubility

(c) Versita Sp. z. o. o. and Springer

We will inform about the volume and issue this paper is officially published.