Acceleration of an unpolarized proton along a uniform magnetic field: Casimir momentum of leptons

Producción CientíficaIt has been recently shown that a chiral molecule accelerates linearly along a spatially uniform magnetic field, as a result of the parity-time symmetry breaking induced in its QED self-interaction. In this work we extend that result to fundamental particles which present EW self-interaction, in which case parity is violated by the EW interaction itself. In particular, we demonstrate that, in a spatially uniform and adiabatically timevarying magnetic field, an unpolarized proton coupled to the leptonic vacuum acquires a kinetic momentum antiparallel to the magnetic field, whereas virtual leptons gain an equivalent Casimir momentum in the opposite direction. That momentum is proportional to the magnetic field and to the square of Fermi’s constant. We prove that the kinetic energy of the proton is a magnetic energy which constitutes a Doppler-shift correction to its EW self-energy

Análise da competição, cooperação e coopetição: uma comparação entre clusters varejistas planejados e não planejados na cidade de São Paulo

Purpose – The purpose of this study was to verify if there are significant differences between planned and unplanned retailer clusters about the competition, cooperation, and coopetition. Design/methodology/approach – An exploratory and quantitative study was carried out by an Exploratory Factor Analysis and Multigroup Analysis-PLS. A questionnaire was applied to 535 companies belonging to the planned and unplanned clusters of the automobile and furniture retail in São Paulo city.Findings – The findings indicate that is possible to identify, in both clusters surveyed, that there is no difference about the cooperation/collaboration analyzed, as well as about the coopetition whether they are low or high. Unlike the competition that presented greater predominance in the unplanned clusters. Thus, we can say that in these clusters, there is a greater deal of competition than cooperation. The research findings also could identify that when a company is inserted in a cluster, it has different strategy for retail businesses relationships of cooperation, competition and coopetition.Originality/value – The major contribution of this study to the literature and administrative implications is the identification that when a company is inserted in a cluster, it has a different strategy for retail businesses relationships of cooperation, competition and coopetition.Objetivo - O objetivo deste estudo foi verificar se existem diferenças significativas entre clusters de varejistas planejados e não planejados quanto à concorrência, cooperação e coopetição.Desenho / metodologia / abordagem - Foi realizado um estudo exploratório, quantitativo por meio de uma Análise Fatorial Exploratória e Análise Multigrupo-PLS. Foi aplicado um questionário com 535 empresas pertencentes aos cluster planejados e não planejados do varejo de automóveis e móveis da cidade de São Paulo.Objetivo - O objetivo deste estudo foi verificar se existem diferenças significativas entre clusters de varejistas planejados e não planejados quanto à concorrência, cooperação e coopetição.Desenho / metodologia / abordagem - Foi realizado um estudo exploratório, quantitativo por meio de uma Análise Fatorial Exploratória e Análise Multigrupo-PLS. Foi aplicado um questionário com 535 empresas pertencentes aos cluster planejados e não planejados do varejo de automóveis e móveis da cidade de São Paulo.Principais resultados – Os principais resultados indicam que foi possível identificar, nos dois clusters pesquisados, que não há diferença quanto à cooperação / colaboração analisada, bem como quanto à coopetição. Ao contrário da competição que apresentou maior predominância nos clusters não planejados. Assim, foi possível afirmar nesses clusters há maior competição do que cooperação. Os resultados da pesquisa também puderam identificar que quando uma empresa está inserida em um cluster, ela possui uma estratégia diferenciada para as relações de cooperação, competição e coopetição dos negócios de varejo.Originalidade / valor - A grande contribuição deste estudo para a literatura e implicações administrativas é a identificação de que quando uma empresa está inserida em um cluster, ela tem uma estratégia diferenciada para as relações de cooperação, competição e coopetição dos negócios varejistas

Topological thermalization via vortex formation in ultra-fast quenches

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Net force on an asymmetrically excited two-atom system from vacuum fluctuations

Física Teórica, Atómica y Óptic

Field Fluctuations and Casimir Energy of 1D-Fermions

Producción CientíficaWe investigate the self-adjoint extensions of the Dirac operator of a massive one-dimensional field of mass m confined in a finite filament of length L. We compute the spectrum of vacuum fluctuations of the Dirac field under the most general dispersionless boundary conditions. We identify its edge states in the mass gap within a set of values of the boundary parameters, and compute the Casimir energy of the discrete normal modes. Two limit cases are considered, namely, that of light fermions with mL 1, and that of heavy fermions for which mL 1. It is found that both positive and negative energies are obtained for different sets of values of the boundary parameters. As a consequence of our calculation we demonstrate that the sign of the quantum vacuum energy is not fixed for exchange-symmetric plates (parity-invariant configurations), unlike for electromagnetic and scalar fields.Ministerio de Economía, Industria y Competitividad (grant MTM2014-57129-C2-1-P)Junta de Castilla y León - Fondo Europeo de Desarrollo Regional (grants VA057U16 and BU229P18)Junta de Castilla y León (grant VA137G18

Recent advances in the management of hypertension

Recently, there have been several reports related to the adequacy of blood pressure (BP) control in high-risk hypertensive patients. These aspects have been reviewed in the recently published reappraisal of the European Society of Hypertension guidelines, and this short review comments on and briefly extends the discussion of this situation. In summary, a low BP goal when cardiorenal disease is advanced can be risky. However, attaining normal BP levels at earlier stages in the cardiorenal continuum is probably totally adequate