Versalhes Redimido?

Os devastadores conflitos que acompanharam a desagregação dos estados multinacionais comunistas na década de 90 estiveram na base das muitas análises que traçaram um paralelo entre duas transições de ordens internacionais: a de 1919 e a de 1989-91. Em ambos os casos, a cultura política das elites envolvidas na criação de novos estados independentes haveria de revelar-se altamente nociva para a constituição de uma ordem política mais liberal no espaço dos antigos impérios. A grande diferença é que, pelo menos, a ordem de Versalhes possuía uma doutrina consistente para lidar com o desafio do nacionalismo étnico, a qual assumiu a forma de um regime internacional de protecção das minorias, garantido pela SDN. Daí, talvez, a tendência recente para a reabilitação do Acordo de Versalhes, depois de durante décadas este ter sido alvo de uma persistente difamação por parte da historiografia internacional

State-Relevant Maxwell's Equation from Kaluza-Klein Theory

We study a five-dimensional perfect fluid coupled with Kaluza-Klein (KK) gravity. By dimensional reduction, a modified form of Maxwell's equation is obtained, which is relevant to the equation of state of the source. Since the relativistic magnetohydrodynamics (MHD) and the 3-dimensional formulation are widely used to study space matter, we derive the modified Maxwell's equations and relativistic MHD in 3+1 form. We then take an ideal Fermi gas as an example to study the modified effect, which can be visible under high density or high energy condition, while the traditional Maxwell's equation can be regarded as a result in the low density and low temperature limit. We also indicate the possibility to test the state-relevant effect of KK theory in a telluric laboratory.Comment: 11 pages, 3 figures; version published in PR

Assembly of sol-gel-grown Li<SUB>x</SUB>CoO<SUB>2</SUB> nanocrystals through electromagnetic irradiation

We report the fabrication of assembled nanostructures from the pre-synthesized nanocrystals building blocks through optical means of exciton formation and dissociation. We demonstrate that Lix CoO2 nanocrystals assemble to an acicular architecture, upon prolonged exposure to ultraviolet-visible radiation emitted from a 125 W mercury vapor lamp, through intermediate excitation of excitons. The results obtained in the present study clearly show how nanocrystals of various materials with band gaps appropriate for excitations of excitons at given optical wavelengths can be assembled to unusual nanoarchitectures through illumination with incoherent light sources. The disappearance of exciton bands due to Li xCoO2 phase in the optical spectrum of the irradiated film comprising acicular structure is consistent with the proposed mechanism of exciton dissociation in the observed light-induced assembly process. The assembly process occurs through attractive Coulomb interactions between charged dots created upon exciton dissociation. Our work presents a new type of nanocrystal assembly process that is driven by light and exciton directed