The extended Conformal Einstein field equations with matter: the Einstein-Maxwell field

A discussion is given of the conformal Einstein field equations coupled with matter whose energy-momentum tensor is trace-free. These resulting equations are expressed in terms of a generic Weyl connection. The article shows how in the presence of matter it is possible to construct a conformal gauge which allows to know \emph{a priori} the location of the conformal boundary. In vacuum this gauge reduces to the so-called conformal Gaussian gauge. These ideas are applied to obtain: (i) a new proof of the stability of Einstein-Maxwell de Sitter-like spacetimes; (ii) a proof of the semi-global stability of purely radiative Einstein-Maxwell spacetimes.Comment: 29 page

Multiplicative Approximations, Optimal Hypervolume Distributions, and the Choice of the Reference Point

Many optimization problems arising in applications have to consider several objective functions at the same time. Evolutionary algorithms seem to be a very natural choice for dealing with multi-objective problems as the population of such an algorithm can be used to represent the trade-offs with respect to the given objective functions. In this paper, we contribute to the theoretical understanding of evolutionary algorithms for multi-objective problems. We consider indicator-based algorithms whose goal is to maximize the hypervolume for a given problem by distributing {\mu} points on the Pareto front. To gain new theoretical insights into the behavior of hypervolume-based algorithms we compare their optimization goal to the goal of achieving an optimal multiplicative approximation ratio. Our studies are carried out for different Pareto front shapes of bi-objective problems. For the class of linear fronts and a class of convex fronts, we prove that maximizing the hypervolume gives the best possible approximation ratio when assuming that the extreme points have to be included in both distributions of the points on the Pareto front. Furthermore, we investigate the choice of the reference point on the approximation behavior of hypervolume-based approaches and examine Pareto fronts of different shapes by numerical calculations

A conformal approach for the analysis of the non-linear stability of pure radiation cosmologies

The conformal Einstein equations for a tracefree (radiation) perfect fluid are derived in terms of the Levi-Civita connection of a conformally rescaled metric. These equations are used to provide a non-linear stability result for de Sitter-like tracefree (radiation) perfect fluid Friedman-Lema\^{\i}tre-Robertson-Walker cosmological models. The solutions thus obtained exist globally towards the future and are future geodesically complete.Comment: 21 page

Financial Integration and Growth -Is Emerging Europe Different?

Using industry-level data, this paper shows that the European transition region benefited much more strongly from financial integration in terms of economic growth than other developing countries in the years preceding the current crisis. We analyze several factors that may explain this finding: financial development, institutional quality, trade integration, political integration, and financial integration itself. The explanation that stands out is political integration. Within the group of transition countries, the effect of financial integration is strongest for countries that are politically closest to the EU. This suggests that political and financial integration are complementary and that political integration can considerably increase the benefits of financial integration.Financial integration; political integration; economic growth; parent banking; European transition economies

Financial integration and growth - Is emerging Europe different?

Using industry-level data, this paper shows that the European transition region benefited much more strongly from financial integration in terms of economic growth than other developing countries in the years preceding the current crisis. We analyse several factors that may explain this finding: financial development, institutional quality, trade integration, political integration, and financial integration itself. The explanation that stands out is political integration. Within the group of transition countries, the effect of financial integration is strongest for countries that are politically closest to the European Union. This suggests that political and financial integration are complementary and that political integration can considerably increase the benefits of financial integration.