Lorentz-violating Yang-Mills theory: discussing the Chern-Simons-like term generation

We analyze the Chern-Simons-like term generation in the CPT-odd Lorentz-violating Yang-Mills theory interacting with fermions. Moreover, we study the anomalies of this model as well as its quantum stability. The whole analysis is performed within the algebraic renormalization theory, which is independent of the renormalization scheme. In addition, all results are valid to all orders in perturbation theory. We find that the Chern-Simons-like term is not generated by radiative corrections, just like its Abelian version. Additionally, the model is also free of gauge anomalies and quantum stable.Comment: 16 pages. No figures. Final version to appear in the Eur.Phys.J.

TRÁGICO NOS TRÓPICOS. TRABALHANDO NIETZSCHE NO BRASIL

Este trabalho é uma exposição dos primeiros resultados de uma pesquisa de mestrado em andamento, cujo objetivo principal é estabelecer uma reflexão sobre a constituição de uma filosofia do trágico no Brasil. A filosofia do trágico nasce na modernidade sob a influência do idealismo alemão e se intensifica, com Nietzsche, como alternativa à racionalidade conceitual da ciência moderna e à hierarquia dos valores proposta pela moral judaico-cristã. Assim como o jovem Nietzsche encontra na Grécia Antiga o fundamento para a elaboração de sua filosofia do trágico – o dionisíaco – é possível que possamos extrair da cosmovisão da cultura yorùbá, que até hoje sobrevive em território africano e em território brasileiro no processo litúrgico do culto aos orìsà, elementos que permitam a formulação do nosso próprio pensamento trágico. Tanto em Nietzsche como na cultura yorùbá, o corpo é valorizado como instância primordial na produção do saber. Assim, deveremos observar como a produção de conceitos a partir da cosmovisão yorùbá pode contribuir como alternativa aos saberes que privilegiam em sua base o que Derrida apontou como “etnocentrismo” e “logocentrismo”

Some numerical verification examples for plane stress elasto-viscoplasticity

This paper presents analytical, semi-analytical and numerical reference examples which can be employed for code verification of elasto-viscoplastic models under plane stress conditions. Mainly because of the overstress function the algorithms traditionally employed in elasto-plastic implementations must be rewritten to correctly impose the plane stress state along with the viscoplastic flow. The viscoplastic formulation presented here considers the strain-rate hardening effects by means of a hardening law that are assumed to have terms depending on the strain rate, which removed can represent a Voce type hardening. The proposed verification tests were employed for the numerical verification of an in-house implementation of the so-called stress-projected procedure inside the finite element method context. Although the focus of this paper is on the stressprojected algorithms the examples presented here can be employed for the verification of other algorithms intended to impose the plane stress state in viscoplasticit

Numerical modeling of strain rate hardening effects on viscoplastic behavior of metallic materials

The main goal of the present work is to provide a finite strain elasticviscoplastic framework to numerically account for strain, strain rate hardening, and viscous effects in cold deformation of metallic materials. The aim is to provide a simple and robust numerical framework capable of modeling the main macroscopic behavior associated with high strain rate plastic deformation of metals. In order to account for strain rate hardening effects at finite strains, the hardening rule involves a rate dependent saturation hardening, and it accounts for linear hardening prevailing at latter deformation stages. The numerical formulation, finite element implementation, and constitutive modeling capabilities are assessed by means of decremental strain rate testing and constant strain rate loading followed by stress relaxation. The numerical results have demonstrated the overall framework can be an efficient numerical tool for simulation of plastic deformation processes where strain rate history effects have to be accounted for

El papel de la voluntad en la teoría de Hannah Arendt sobre los conflictos políticos

Hannah Arendt’s work is notably ambiguous in handling the concept of will. On the one hand, willing appears as an anti-political faculty; on the other, it is named as the spring of political action. This paper asks what does this shift mean to her political theory —hoping that it could also help us to think our current political conflicts. The main argument is that will’s consistency with the plurality of public-political life becomes intelligible only if we have in mind its contentious feature as well as its bonding role among the several faculties that compose a multiple self. However, the anti-political notion of the will as a command that imposes itself as a sovereign decision seems hard to avoid. I conclude by suggesting that Arendt’s reappraisal removes its arbitrary and violent character by means of what she calls the transformation of will into love.La obra de Hannah Arendt es notablemente ambigua en el manejo del concepto de voluntad. Por un lado, la voluntad aparece como una facultad antipolítica; por el otro, es nombrada como la fuente de la acción política. Este artículo pregunta qué significa este cambio para su teoría política, con la esperanza de que esto también nos ayude a pensar nuestros conflictos políticos actuales. El argumento principal es que la coherencia de la voluntad con la pluralidad de la vida político-pública sólo se hace inteligible si tenemos en mente su carácter contencioso y además su papel de vinculación entre las diversas facultades que componen un múltiple self. Sin embargo, la noción antipolítica de la voluntad como un comando que se impone tal cual una decisión soberana parece difícil de evitar. Concluyo sugiriendo que la reevaluación de Arendt elimina su carácter arbitrario y violento por medio de lo que ella llama la transformación de la voluntad en amor

Discretization-dependent model for weakly connected excitable media

Pattern formation has been widely observed in extended chemical and biological processes. Although the biochemical systems are highly heterogeneous, homogenized continuum approaches formed by partial differential equations have been employed frequently. Such approaches are usually justified by the difference of scales between the heterogeneities and the characteristic spatial size of the patterns. Under different conditions, for example, under weak coupling, discrete models are more adequate. However, discrete models may be less manageable, for instance, in terms of numerical implementation and mesh generation, than the associated continuum models. Here we study a model to approach discreteness which permits the computer implementation on general unstructured meshes. The model is cast as a partial differential equation but with a parameter that depends not only on heterogeneities sizes, as in the case of quasicontinuum models, but also on the discretization mesh. Therefore, we refer to it as a discretization-dependent model. We validate the approach in a generic excitable media that simulates three different phenomena: the propagation of action membrane potential in cardiac tissue, in myelinated axons of neurons, and concentration waves in chemical microemulsions.We acknowledge the support from CAPES, grant 88881.065002/2014-01 of the Brazilian program Science without borders, FAPEMIG, CNPq, UFJF, and from MINECO of Spain under the Ramon y Cajal program, grant number RYC-2012-11265Peer ReviewedPostprint (published version