Charges and fluxes in Maxwell theory on compact manifolds with boundary

We investigate the charges and fluxes that can occur in higher-order Abelian gauge theories defined on compact space-time manifolds with boundary. The boundary is necessary to supply a destination to the electric lines of force emanating from brane sources, thus allowing non-zero net electric charges, but it also introduces new types of electric and magnetic flux. The resulting structure of currents, charges, and fluxes is studied and expressed in the language of relative homology and de Rham cohomology and the corresponding abelian groups. These can be organised in terms of a pair of exact sequences related by the Poincare-Lefschetz isomorphism and by a weaker flip symmetry exchanging the ends of the sequences. It is shown how all this structure is brought into play by the imposition of the appropriately generalised Maxwell's equations. The requirement that these equations be integrable restricts the world-volume of a permitted brane (assumed closed) to be homologous to a cycle on the boundary of space-time. All electric charges and magnetic fluxes are quantised and satisfy the Dirac quantisation condition. But through some boundary cycles there may be unquantised electric fluxes associated with quantised magnetic fluxes and so dyonic in nature.

Nonlocal charges for bonus yangian symmetries of Super-Yang-Mills

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Basicities of primary arylamines and calculated amine nitrogen electronic charges

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

THE CONSERVED CHARGES AND INTEGRABILITY OF THE CONFORMAL AFFINE TODA MODELS

We construct infinite sets of local conserved charges for the conformal affine Toda model. The technique involves the abelianization of the two-dimensional gauge potentials satisfying the zero-curvature form of the equations of motion. We find two infinite sets of chiral charges and apart from two lowest spin charges, all the remaining ones do not possess chiral densities. Charges of different chiralities Poisson commute among themselves. We discuss the algebraic properties of these charges and use the fundamental Poisson bracket relation to show that the charges conserved in time are in involution. Connections to other Toda models are established by taking particular limits.

Magnetic field release of trapped charges in poly(fluorenylenevinylene)s

We have measured the effect of an applied magnetic field on the current through thin films of two different organic conjugated polymers that have previously shown to exhibit magnetoresistance, poly(9,9-dioctyl-1,4-fluorenylenevinylene) and poly(9,9-dioctyl-2,7-fluorenylenevinylene). The results show that the magnetic field releases trapped charges from inside the material and enhances the current. We have also performed optical absorption experiments on these polymer films under applied voltage and magnetic field. The results show that the magnetic field produces a change in the optical absorption in the low-energy range associated with deep traps and only under conditions when these traps are likely charged. These two results provide a strong case for the release of trapped charges caused by the magnetic field as being the cause of the magneto resistance in these polymers and possibly in other organic materials where magnetoresistance was recently observed. (c) 2007 Elsevier B.V. All rights reserved.

DO INERTIAL ELECTRIC CHARGES RADIATE WITH RESPECT TO UNIFORMLY ACCELERATED OBSERVERS

We revisit the long standing problem of analyzing an inertial electric charge from the point of view of uniformly accelerated observers in the context of semi-classical gravity. We Choose a suitable set of accelerated observers with respect to which there is no photon emission coming from the inertial charge. We discuss this result against previous claims.

THE ALGEBRA OF NONLOCAL CHARGES IN NONLINEAR SIGMA-MODELS

We obtain the exact classical algebra obeyed by the conserved non-local charges in bosonic non-linear sigma models. Part of the computation is specialized for a symmetry group O(N). As it turns out the algebra corresponds to a cubic deformation of the Kac-Moody algebra. We generalize the results for the presence of a Wess-Zumino term. The algebra is very similar to the previous one, now containing a calculable correction of order one unit lower. The relation with Yangians and the role of the results in the context of Lie-Poisson algebras are also discussed.

Structural and Electronic Properties of Lithiated SnO2. A Periodic DFT Study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ramond-ramond central charges in the supersymmetry algebra of the superstring

The free action for the massless sector of the type II superstring was recently constructed using closed Ramond-Neveo-Schwarz superstring field theory. The supersymmetry transformations of this action are shown to satisfy an N = 2 D = 10 supersymmetry algebra with Ramond-Ramond central charges.

BRST cohomology and nonlocal conserved charges

A relation is found between nonlocal conserved charges in string theory and certain ghost-number two states in the BRST cohomology. This provides a simple proof that the nonlocal conserved charges for the superstring in an AdS 5 × S5 background are BRST-invariant in the pure spinor formalism and are κ-symmetric in the Green-Schwarz formalism. © SISSA/ISAS 2005.

Fractional fermion charges induced by axial-vector and vector gauge potentials and parity anomaly in planar graphenelike structures

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Demochargia: Dilma Rousseff e seu primeiro ano de mandato pelas charges jornalísticas

Pós-graduação em Comunicação - FAAC

Charges: um olhar estereotipado dos professores

O presente trabalho de conclusão de curso, intitulado Charges um olhar estereotipado dos professores, é o resultado de um interesse sobre esse tipo de arte gráfica desde a adolescência atrelada à curiosidade sobre a imagem construída historicamente sobre os professores e sobre sua vida profissional. Este trabalho tem por objetivo analisar os estereótipos que são atribuídos aos professores nas charges procurando observar características de gênero, de vestuário e de caráter psicológico. Para atingir esse objetivo, teve-se o intuito de utilizar como material de pesquisa as charges do autor italiano Francesco Tonucci que publicou mais de mil charges na Itália e na Espanha. Esse autor procura abordar em seus desenhos temas que mostram a educação formal e informal em seu país, criticando à forma como a educação é tratada, essas realidades se encaixam com a do Brasil em muitos aspectos, e são estes aspectos que forneceram dados para analise. Para desenvolver essa pesquisa se utilizara a abordagem qualitativa, seguindo a metodologia de pesquisa documental e bibliográfica. Neste trabalho foram observados os estereótipos atribuídos aos professores e discutiu-se que imagem é transmitida desse profissional por esse suporte de leitura tão popular. Para aprofundar a questão dos estereótipos se realizou leituras de artigos que abordaram a questão dos estereótipos no contexto educacional, além de fontes que forneceram explicações sobre o fundamento histórico que deram razões para que esses estereótipos acontecessem. Quanto às charges se realizou um breve apanhado histórico de como esse tipo de arte gráfica surgiu e porque faz tanto sucesso nos meios de comunicação