Operator Product on Locally Symmetric Spaces of Rank One and the Multiplicative Anomaly

The global multiplicative properties of Laplace type operators acting on irreducible rank one symmetric spaces are considered. The explicit form of the multiplicative anomaly is derived and its corresponding value is calculated exactly, for important classes of locally symmetric spaces and different dimensions.Comment: Int. Journal of Modern Physics A, vol. 18 (2003), 2179-218

Massive scalar field near a cosmic string

The $\zeta$ function of a massive scalar field near a cosmic string is computed and then employed to find the vacuum fluctuation of the field. The vacuum expectation value of the energy-momentum tensor is also computed using a point-splitting approach. The obtained results could be useful also for the case of self-interacting scalar fields and for the finite-temperature Rindler space theory.Comment: 15 pages, standard LaTeX, no figures. Reference [14] correcte

Cosmic String Wakes in Scalar-Tensor Gravities

The formation and evolution of cosmic string wakes in the framework of a scalar-tensor gravity are investigated in this work. We consider a simple model in which cold dark matter flows past an ordinary string and we treat this motion in the Zel'dovich approximation. We make a comaprison between our results and previous results obtained in the context of General Relativity. We propose a mechanism in which the contribution of the scalar field to the evolution of the wakes may lead to a cosmological observation.Comment: Replaced version to be published in the Classical and Quantum Gravit

Thermal fluctuations of a quantized massive scalar field in Rindler background

Thermal fluctuations for a massive scalar field in the Rindler wedge are obtained by applying the point-splitting procedure to the zero temperature Feynman propagator in a conical spacetime. Renormalization is implemented by removing the zero temperature contribution. It is shown that for a field of non vanishing mass the thermal fluctuations, when expressed in terms of the local temperature, do not have Minkowski form. As a by product, Minkowski vacuum fluctuations seen by an uniformly accelerated observer are determined and confronted with the literature.Comment: 10 pages; Latex fil

Partition Functions of Three-Dimensional Quantum Gravity and the Black Hole Entropy

We analyze aspects of the holographic principle relevant to the quantum gravity partition functions in Euclidean sector of AdS$_3$. The sum of the known contributions to the partitions functions can be presented exactly, including corrections, in the form where the Patterson-Selberg zeta function involves.Comment: 8 pages, no figures. Some misprints have been corrected, title changed. To appear in the J. Phys. A (2009

Orbifold Compactification and Solutions of M--Theory from Milne Spaces

In this paper, we consider solutions and spectral functions of M-theory from Milne spaces with extra free dimensions. Conformal deformations to the metric associated with the real hyperbolic space forms are derived. For the three-dimensional case, the orbifold identifications $SL(2,{\mathbb Z}+i{\mathbb Z})/\{\pm Id\}$, where $Id$ is the identity matrix, is analyzed in detail. The spectrum of a eleven-dimensional field theory can be obtained with the help of the theory of harmonic functions in the fundamental domain of this group and it is associated with the cusp forms and the Eisenstein series. The supersymmetry surviving for supergravity solutions involving real hyperbolic space factors is briefly discussed.Comment: 14 pages, no figures. To appear in The European Physical Journal C - Particles and Field

Electrostatic self-force in (2+1)-dimensional cosmological gravity

Point sources in (2+1)-dimensional gravity are conical singularities that modify the global curvature of the space giving rise to self-interaction effects on classical fields. In this work we study the electrostatic self-interaction of a point charge in the presence of point masses in (2+1)-dimensional gravity with a cosmological constant.Comment: 9 pages, Late

Vacuum Polarization of a Charged Massless Scalar Field on Cosmic String Spacetime in the Presence of a Magnetic Field

In this paper we consider a charged massless scalar quantum field operator in the spacetime of an idealized cosmic string, i.e., an infinitely long, straight and static cosmic string, which presents a magnetic field confined in a cylindrical tube of finite radius. Three distinct situations are taking into account in this analysis: {\it{i)}} a homogeneous field inside the tube, {\it{ii)}} a magnetic field proportional to $1/r$ and {\it{iii)}} a cylindrical shell with $\delta$-function. In these three cases the axis of the infinitely long tube of radius $R$ coincides with the cosmic string. In order to study the vacuum polarization effects outside the tube, we explicitly calculate the Euclidean Green function associated with this system for the three above situations, considering points in the region outside the tube.Comment: 26 pages, LaTex format, 3 figure

Parâmetros leucocitários de caprinos da raça Moxotó criados no semi-árido cearense.

A influência de algumas variáveis ambientais sobre a fisiologia animal podem ocasionar evidentes oscilações nos elementos constituintes do hemograma em especial do leucograma. Diante da importância das raças caprinas nativas criadas na região Nordeste, objetivou-se com esse estudo conhecer os valores do leucograma de caprinos da raça Moxotó criados no semi-árido cearense, visando determinar os parâmetros específicos para a raça, durante os períodos seco e chuvoso. Foram avaliados 15 animais, sendo cinco machos e dez fêmeas. As colheitas de sangue, num total de 60 amostras, foram realizadas no período da manhã, nos meses de abril e setembro, durante dois anos. Foi possível observar que os valores médios obtidos neste estudo encontram-se dentro da faixa de normalidade citada na literatura, exceto para os valores de bastões, segmentados do machos no período chuvoso e eosinófilos das fêmeas no período seco e chuvoso, que estão acima dos valores considerados normais. Foi observada diferença estatística significativa entre os machos e fêmeas no período seco quanto aos valores de leucócitos totais e segmentados. Observou-se também diferença estatística significativa entre os períodos seco e chuvoso quanto aos valores absolutos de monócitos. Apesar deste estudo, ainda é necessária a realização de maispesquisas com um número maior de animais para a determinação dos parâmetros normais