Neutron Stars with Hyperons subject to Strong Magnetic Field

Neutron stars are one of the most exotic objects in the universe and a unique laboratory to study the nuclear matter above the nuclear saturation density. In this work, we study the equation of state of the nuclear matter within a relativistic model subjected to a strong magnetic field. We then apply this EoS to study and describe some of the physical characteristics of neutron star, especially the mass-radius relation and chemical compositions. To study the influence of a the magnetic field and the hyperons in the stellar interior, we consider altogether four solutions: two different values of magnetic field to obtain a weak and a strong influence, and two configurations: a family of neutron stars formed only by protons, electrons and neutrons and a family formed by protons, electrons, neutrons, muons and hyperons. The limit and the validity of the results found are discussed with some care. In all cases the particles that constitute the neutron star are in $\beta$ equilibrium and zero total net charge. Our work indicates that the effect of a strong magnetic field has to be taken into account in the description of magnetars, mainly if we believe that there are hyperons in their interior, in which case, the influence of the magnetic field can increase the mass by more than 10%. We have also seen that although a magnetar can reach 2.48$M_{\odot}$, a natural explanation of why we do not know pulsars with masses above 2.0$M_{\odot}$ arises. We also discuss how the magnetic field affects the strangeness fraction in some standard neutron star masses and, to conclude our paper, we revisit the direct URCA process related to the cooling of the neutron stars and show how it is affected by the hyperons and the magnetic field.Comment: 16 pages, 8 figure

Integers : irreducible guides in the search for a unified theory

The notion of final theory results from a contrasting understanding of physical reality. Currently, different approaches aim to unify the four forces of nature and discuss whether a final theory may be possible. A key feature of a final theory is irreducibility, however this property has not been seriously exploited. In the paper we present an irreducible mathematical theory that describes physical systems in terms of formation processes of integer relations. The theory has integers and integer relations as the basic elements and is irreducible, because the formation processes are completely controlled by arithmetic. We suggest properties of the formationprocesses as irreducible guides in the search for a unified theory

IX Congresso Brasileiro de Biomecânica (Gramado, 2001) - Folder de divulgação

Folder de divulgação do IX Congresso Brasileiro de Ciências do Esporte realizado em Gramado, RS, nos dias 29 de maio e 1 de junho de 2001 O documento integra o acervo institucional da Escola de Educação Física.Material de divulgação do evento.DoaçãoEscola de Educação Físic

IX Congresso Brasileiro de Biomecânica (Gramado, 2001) - Folder de divulgação

Folder de divulgação do IX Congresso Brasileiro de Ciências do Esporte realizado em Gramado, RS, nos dias 29 de maio e 1 de junho de 2001 O documento integra o acervo institucional da Escola de Educação Física.Material de divulgação do evento.DoaçãoEscola de Educação Físic

Brazilian Journal of Physics On the calculation of inner products of Schur functions

Two methods for calculating inner products of Schur functions in terms of outer products and plethysms are given and they are easy to implement on a machine. One of these is derived from a recent analysis of the S