Corrigendum to “Growth conditions, Riemannian completeness and Lorentzian causality” [J. Geom. Phys. 62 (2012) 604–612]

Corrigendum to: “Removing ECG Artifact from the Surface EMG Signal Using Adaptive Subtraction Technique” published in J Biomed Phys Eng 2014; 4(1):31-38

Variational Equations on Mixed Riemannian-lorentzian Metrics

A class of elliptic-hyperbolic equations is placed in the context of a geometric variational theory, in which the change of type is viewed as a change in the character of an underlying metric. A fundamental example of a metric which changes in this way is the extended projective disc, which is Riemannian at ordinary points, Lorentzian at ideal points, and singular on the absolute. Harmonic fiel...

Harmonic fields on mixed Riemannian-Lorentzian manifolds

The extended projective disc is Riemannian at ordinary points, Lorentzian at ideal points, and singular on the absolute. Harmonic fields on this metric can be interpreted as the hodograph image of extremal surfaces in Minkowski 3-space. This suggests an approach to generalized Plateau problems in 3-dimensional space-time via Hodge theory on the extended projective disc. Boundary-value problems ...

On Lorentzian causality with continuous metrics

We present a systematic study of causality theory on Lorentzian manifolds with continuous metrics. Examples are given which show that some standard facts in smooth Lorentzian geometry, such as light-cones being hypersurfaces, are wrong when metrics which are merely continuous are considered. We show that existence of time functions remains true on domains of dependence with continuous metrics, ...

Public Expenditure and Economic Growth in Nigeria (A Granger Causality Approach) 1983-2012

This paper examines the impact of government expenditure on the Nigerian economy for the period 1983 - 2012. The government expenditure components used as the explanatory variables in the model are: expenditures on Health, Education, Defense, Agriculture and Transportation and Communication. The Gross Domestic Product (GDP) was used as a parameter for measuring economic growth. In order to esta...