Seminal magnetic fields from Inflato-electromagnetic Inflation

We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot provide us with the desired magnetic seeds. We show that special fields without propagation on the extra non-compact dimension are needed to arrive to appreciable magnetic strengths. We also identify a new magnetic tensor field $B_{ij}$ in this kind of extra dimensional theories. Our results are in very good agreement with observational requirements, in particular from TeV Blazars and CMB radiation limits we obtain that primordial cosmological magnetic fields should be close scale invariance.Comment: Improved version. arXiv admin note: text overlap with arXiv:1007.3891 by other author

Optimum Saving and Growth: Harrod on Dynamic Welfare Economics

In the 1960s and 1970s Harrod shifted the emphasis of his research in economic dynamics from the study of business cycles (instability principle) to the investigation of the growth process. As part of that, he restated his concept of the natural growth rate as an optimum welfare rate. The present paper examines Harrod's dynamic welfare economics, built around his concept of optimum saving developed as a reaction to Ramsey's approach to capital accumulation. It is shown that, according to Harrod, the saving rate does not affect the long-run growth rate of per capita income, which is determined by technical progress. Moreover, the economy will grow at the natural (full employment) rate only if economic policy is able to bring saving to its "optimum" level in macroeconomic equilibrium. Harrod's interest in optimal growth was motivated by his double concern with growth policy in mature economies and economic development in poor countries

Does the World Real Interest Rate Affect the Real Exchange Rate? The South East Asian Experience

We analyse the consequences of US real interest rate rises on the real exchange rate (RER) in a two-good overlapping generations model of a semi-small open economy. The equilibrium RER depreciates (appreciates) when the world interest rate increases in a debtor (creditor) country. We then study empirically the reaction of the RER in a set of South East Asian (SEA) countries to shocks in US real interest rates. The results support the conclusions of the theory model at least for Singapore, Thailand and South Korea during the period 1980-2001

New insights from a structural economic dynamic approach to balance of payments constrained growth

In this paper it is shown that once-for-all variations in the level of the exchange rate may play an important role in the sectoral composition of the economy and this fact has important implications in terms of a disaggregated version of the Thirlwall’s law even if the argument of the quantitative unimportance of relative price movements holds. The growth rate of a country is then shown to be affected by once-for-all movements in the level of nominal exchange rates and the concept of a natural exchange rate is introduced

Testing Unemployment Theories: A Multivariate Long Memory Approach

This paper investigates the empirical relevance of different unemployment theories in three major economies, namely the UK, the US and Japan, by estimating the degree of dependence in the unemployment series. Both univariate and multivariate long memory methods are used. The results vary depending on whether the former or the latter approach is followed. Specifically, when taking a univariate approach, the unit root null cannot be rejected in case of the UK and Japanese unemployment series, and some degree of mean reversion (d < 1) is found in the case of the US unemployment rate. When applying multivariate methods instead, higher orders of integration are still found for the UK and Japanese series, but the NAIRU hypothesis cannot be rejected in the case of the US

The Role of Mobile Phones in Governance-Driven Technology Exports in Sub-Saharan Africa

This study assesses how the mobile phone influences governance to improve information and communication technology (ICT) exports in Sub-Saharan Africa with data from 2000-2012. The empirical evidence is based on Generalised Method of Moments and three main governance concepts are used, namely: (i) institutional (comprising the rule of law and corruption-control); (ii) political (involving political stability/no violence and voice & accountability) and (iii) economic (including regulation quality and government effectiveness) governance. The following findings are established. First, there are positive net effects on ICT goods exports from independent interactions between mobile phones and ‘political stability’ ‘voice and accountability’ and corruption-control. Second, significant net effects are not apparent from independent interactions between mobile phones and government effectiveness, regulation quality and the rule of law. Theoretical and practical implications are discussed