Booms and Busts in Latin America: The Role of External Factors

This paper analyzes the relevance of external factors in average quarterly GDP growth for 1990-2006 in the seven largest Latin American countries (LAC7). Modeling the relationship between LAC7 GDP and several external factors, it is found that those factors account for a significant share of variance in LAC7 GDP growth, and that external shocks produce significant responses. Likewise, a significant share of recent LAC7 growth performance can be explained by an external factor “tailwind. ” Also evaluated is the impact of deterioration in external financial conditions. Finally, the relevance of these findings for policy evaluation is emphasized. Growth performance, the strength or weakness of macroeconomic fundamentals and the impact of domestic macro and micro policies on growth can only be properly appraised by first filtering out the effects of external factors.

The embedding of the spacetime in five dimensions: an extension of Campbell-Magaard theorem

We extend Campbell-Magaard embedding theorem by proving that any n-dimensional semi-Riemannian manifold can be locally embedded in an (n+1)-dimensional Einstein space. We work out some examples of application of the theorem and discuss its relevance in the context of modern higher-dimensional spacetime theories.Comment: 22pages, Revte

Booms and busts in Latin America: The role of external factors

This paper analyzes the relevance of external factors in average quarterly GDP growth for 1990-2006 in the seven largest Latin American countries (LAC7). Modeling the relationship between LAC7 GDP and several external factors, it is found that those factors account for a significant share of variance in LAC7 GDP growth, and that external shocks produce significant responses. Likewise, a significant share of recent LAC7 growth performance can be explained by an external factor 'tailwind'. Also evaluated is the impact of deterioration in external financial conditions. Finally, the relevance of these findings for policy evaluation is emphasized. Growth performance, the strength or weakness of macroeconomic fundamentals and the impact of domestic macro and micro policies on growth can only be properly appraised by first filtering out the effects of external factors

The embedding of the spacetime in five-dimensional spaces with arbitrary non-degenerate Ricci tensor

We discuss and prove a theorem which asserts that any n-dimensional semi-Riemannian manifold can be locally embedded in a (n+1)-dimensional space with a non-degenerate Ricci tensor which is equal, up to a local analytic diffeomorphism, to the Ricci tensor of an arbitrary specified space. This may be regarded as a further extension of the Campbell-Magaard theorem. We highlight the significance of embedding theorems of increasing degrees of generality in the context of higher dimensional spacetimes theories and illustrate the new theorem by establishing the embedding of a general class of Ricci-flat spacetimes

Confinement and stability of the motion of test particles in thick branes

We consider the motion of test particles in a thick brane version of Randall-Sundrum type II model. It is known that gravity alone cannot explain the confinement of test particles in this kind of brane. In this paper we show that a stable confinement in a domain wall is possible by admitting a direct interaction between test particles and a scalar field. This interaction is implemented by a modification of the Lagrangian of the particle which is inspired by a Yukawa-type interaction between fermions and scalar fields.Comment: 1 figure. Extended analysis to treat general thick branes RSII-type. Added reference

Spacetime Measurements in Kaluza-Klein Gravity

We extend the classical general relativistic theory of measurement to include the possibility of existence of higher dimensions. The intrusion of these dimensions in the spacetime interval implies that the inertial mass of a particle in general varies along its worldline if the observations are analyzed assuming the existence of only the four spacetime dimensions. The variations of mass and spin are explored in a simple 5D Kaluza-Klein model.Comment: LaTeX, 12 pages, no figures, 2 references added, to appear in Phys. Lett.

Embedding of the Brane into Six Dimensions

Embedding of the brane metric into Euclidean (2+4)-space is found. Brane geometry can be visualized as the surface of the hyper-sphere in six dimensions which 'radius' is governed by the cosmological constant. Minkowski space in this picture is lied on the intersection of this surface with the plane formed by the extra space-like and time-like coordinates.Comment: 3 pages, LaTeX, no figures, one citation was eddie

Proposed specifiers for conduct disorder-short version (PSCD-SV): psychometric properties, concurrent correlates and parenting predictors

The present study aims to further examine the four-factor model of psychopathy in adolescence with a new alternate model for the assessment of psychopathic traits and conduct disorder (CD): The Proposed Specifiers for Conduct Disorder-Short version (PSCD-SV). Data were collected in a sample of 414 adolescents (49.2% females) aged 12–15 at the first assessment who were then followed-up 2 years later. Results supported the usefulness of the PSCD-SV to assess the broader construct of psychopathy showing good psychometric properties, including adequate reliability and validity, while accounting for all its dimensions. In addition, the study showed close associations between psychopathic traits and adolescent behavioral, emotional and psychosocial maladjustment. Finally, the findings elucidated the PSCD’s connection to parental support and psychological control, and reinforced the potential role of parenting practices as predictors that can act as mechanisms of change in the development of psychopathy. Overall, current findings shed light on conceptual and developmental models of psychopathy that may have implications for assessment, diagnostic classification, prevention, and interventionOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was partially funded by Xunta de Galicia under the Programa de Axudas á Etapa Posdoutoral (Consellería de Cultura, Educación e Ordenación Universitaria; 2017, 2019 and 2021) and the Consolidation and structuring of competitive research units and other promotional actions in the universities of the SUG; GRC, 2018S

Noncommutativity in quantum cosmology and the Hierarchy problem

We study the quantum cosmology of an empty (4+1)-dimensional Kaluza-Klein cosmology with a negative cosmological constant and a FRW type metric with two scale factors, one for 4-D universe and the other for one compact extra dimension. By assuming the noncommutativity in the corresponding mini-superspace we suggest a solution for the Hierarchy problem, at the level of Wheeler-DeWitt equation.Comment: 7 pages; Title, abstract and text changed; references added; to appear in PL

The seed of magnetic monopoles in the early inflationary universe from a 5D vacuum state

Starting from a 5D Riemann flat metric, we have induced an effective 4D Hermitian metric which has an antisymmetric part which is purely imaginary. We have worked an example in which both, non-metricity and contorsion are zero. We obtained that the production of monopoles should be insignificant at the end of inflation and the tensor metric should come asymptotically diagonal and describing a nearly 4D de Sitter expansion.Comment: Version accepted in Physics Letters