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Teresina, Brazil

Faria F.F.,State University of Piaui
European Physical Journal C | Year: 2016

We first find the linear approximation of the second plus fourth order derivative massive conformal gravity action. Then we reduce the linearized action to separated second order derivative terms, which allows us to quantize the theory by using the standard first order canonical quantization method. It is shown that quantum massive conformal gravity is renormalizable but has ghost states. A possible decoupling of these ghost states at high energies is discussed. © 2016, The Author(s).

Formiga J.B.,State University of Piaui
General Relativity and Gravitation | Year: 2015

When dealing with a spacetime, one usually searches for singularities, black holes, white holes and wormholes due to their importance to the motion of particles. There is a family of solution of the Brans–Dicke vacuum equations that has not been fully studied from this perspective. In this paper, I study some properties of this family and find the complete set of solutions that avoids singularity at the point where the metric diverges or degenerates. The possible changes in the metric signature when passing through this point is analyzed. In addition, I also study the radial geodesics and obtain the solutions of some particular cases. © 2015, Springer Science+Business Media New York.

Faria F.F.,State University of Piaui
Advances in High Energy Physics | Year: 2014

We construct a massive theory of gravity that is invariant under conformal transformations. The massive action of the theory depends on the metric tensor and a scalar field, which are considered the only field variables. We find the vacuum field equations of the theory and analyze its weak-field approximation and Newtonian limit. Copyright © 2014 F. F. Faria.

Barreto J.O.M.,Secretaria Municipal de Saude de Piripiri | Nery I.S.,Federal University of Piaui | Costa M.S.C.,State University of Piaui
Cadernos de Saude Publica | Year: 2012

Hospitalizations for some health conditions can be reduced by timely primary care with appropriate quality, especially in children. This study analyzed the trend in hospitalizations in children under five years of age in Piauí State, Brazil, from 2000 to 2010, according to groups of causes (ICD- 10) and hospital admissions in 2010, based on the Brazilian List of Hospitalizations for Primary Care-Sensitive Conditions. The objectives were to identify changes in the hospital morbidity profile and to discuss their relationship to expansion of the Family Health Strategy (FHS) in the State. Piauí showed the highest proportional expansion of the FHS in Brazil, reaching an estimated coverage of 97.2% in 2010. From 2000 to 2010, there was a reduction in the hospitalization frequency and rates in children under five years, but the proportion of hospitalizations in the leading groups of causes persisted or increased during the decade. In 2010, 60% of hospitalizations in children under five years were for causes that are sensitive to primary care, especially infectious gastroenteritis, respiratory infections, and asthma.

Formiga J.B.,State University of Piaui
International Journal of Theoretical Physics | Year: 2014

Recently, an extension of teleparallelism to a Weyl geometry which allows us to easily establish conformal invariance and "geometrize" electromagnetism has been presented. In this paper, I extend a result which concerns the existence of the Schwarzschild solution to a particular class of this extension. In addition, I obtain the field equations of some models based on this extension, including the one which is equivalent to Einstein's field equations with a massless scalar field. © 2014 Springer Science+Business Media New York.

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