5,376 research outputs found
Topological Vertex, String Amplitudes and Spectral Functions of Hyperbolic Geometry
We discuss the homological aspects of the connection between quantum string
generating function and the formal power series associated to the dimensions of
chains and homologies of suitable Lie algebras. Our analysis can be considered
as a new straightforward application of the machinery of modular forms and
spectral functions (with values in the congruence subgroup of ) to the partition functions of Lagrangian branes, refined vertex and open
string partition functions, represented by means of formal power series that
encode Lie algebra properties. The common feature in our examples lies in the
modular properties of the characters of certain representations of the
pertinent affine Lie algebras and in the role of Selberg-type spectral
functions of an hyperbolic three-geometry associated with -series in the
computation of the string amplitudes.Comment: Revised version. References added, results remain unchanged. arXiv
admin note: text overlap with arXiv:hep-th/0701156, arXiv:1105.4571,
arXiv:1206.0664 by other author
Scalar and Spinor Particles in the Spacetime of a Domain Wall in String Theory
We consider scalar and spinor particles in the spacetime of a domain wall in
the context of low energy effective string theories, such as the generalized
scalar-tensor gravity theories. This class of theories allows for an arbitrary
coupling of the wall and the (gravitational) scalar field. First, we derive the
metric of a wall in the weak-field approximation and we show that it depends on
the wall's surface energy density and on two post-Newtonian parameters. Then,
we solve the Klein-Gordon and the Dirac equations in this spacetime. We obtain
the spectrum of energy eigenvalues and the current density in the scalar and
spinor cases, respectively. We show that these quantities, except in the case
of the energy spectrum for a massless spinor particle, depend on the parameters
that characterize the scalar-tensor domain wall.Comment: LATEX file, 21 pages, revised version to appear in Phys. Rev.
Gerenciamento de resíduos sólidos em comunidades rurais do Estado do Amazonas: estudo de caso na comunidade de Manairão.
Este trabalho busca sensibilizar as famílias de agricultores sobre as forma corretas do descarte dos resíduos sem afetar o meio ambiente e sobre as normas da reciclagem e elucidar os problemas sofridos nas comunidades com relação ao lixo; nas comunidades examinadas não havia coletor de lixo, levando o proprietário a uma única solução, jogá-lo na sua propriedade
Variabilidade molecular (RFLPS) em ciclos de seleção da população de milho "Iowa Stiff Stalk Synthetic".
Divergência molecular (RFLPs) entre ciclos de seleção na população de milho "Iowa Stiff Stalk Synthetic".
Avaliação do impacto de 14 ciclos de seleção recorrente nas freqüências alélicas (RFLPs) da população de milho "Iowa Stiff Stalk Synthetic".
Rastreamento da distância genética entre linhagens progenitoras e ciclos de seleção na população de milho "Iowa Stiff Stalk Synthetic".
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