An alternative to the Allen-Cahn phase field model for interfaces in solids - numerical efficiency

The derivation of the Allen-Cahn and Cahn-Hilliard equations is based on the Clausius-Duhem inequality. This is not a derivation in the strict sense of the word, since other phase field equations can be fomulated satisfying this inequality. Motivated by the form of sharp interface problems, we formulate such an alternative equation and compare the properties of the models for the evolution of phase interfaces in solids, which consist of the elasticity equations and the Allen-Cahn equation or the alternative equation. We find that numerical simulations of phase interfaces with small interface energy based on the alternative model are more effective then simulations based on the Allen-Cahn model.Comment: arXiv admin note: text overlap with arXiv:1505.0544

Destruction of quantum coherence and wave packet dynamic

The main aim of this article is to discuss characteristic physical phenomena which govern the destruction of quantum coherence of material wave packets.Comment: to be published in `The Physics and Chemistry of Wave Packets', edited by J. A. Yeazell and T. Uzer (Wiley, N. Y.

A systematic study of two particle correlations from NA49 at CERN SPS

A systematic study of two particle correlations measured by the NA49 experiment is summarized. Radii from Bose Einstein interferometry have been determined separately in different parts of phase space, for different collision systems and at different incident beam energies. Moreover, first results of a new method of accessing space-time asymmetries in the emission of particles by means of non identical particle correlations are presented.Comment: 4 pages 3 figures publ. in proc. of QM99, Torino It Nuclear Physics

Where Turkey stands in Europe and why it should be admitted to the EU

Turkeys position relative to Europe is analyzed from three different perspectives, i.e (i) the semi-official perspective of the Copenhagen criteria, the Maastricht criteria and the Lisbon strategy, (ii) the perspective of comparative surveys, and (iii) the perspective of key European worries regarding future strains on cohesion funds and the complex relationship of the Turkish population to European values. It is shown that Turkeys standing in international comparisons of good governance has been improving in recent years and that the country is on a path of convergence with the Maastricht criteria. Turkey falls considerably short, however, of the employment and education goals of the Lisbon agenda. Comparative surveys show the Turkish population to have not only a low standard of living, but also a very low level of satisfaction with life and with public services, to have comparatively little trust in other people and a low level of civic engagement, and to nourish traditional attitudes concerning religious beliefs, womens rights and gender roles. Since Turkeys admission to the EU would enlarge the EU population by 15 %, but economic output by less than 3 %, Turkeys accession would severely strain EU cohesion funds. Despite these reservations, Turkeys admission to the Union is here advocated for three reasons: (1) Risks of a fundamentalist backlash against Europe would considerably increase if the long-standing accession promise were not kept. (2) Given that the country is entering a very favourable demographic phase for about 2-3 decades, there is considerable economic opportunity with a vast growth potential. (3) Since the recent Eastern enlargements have already decided the debate between federalists and inter-governmentalists in favour of the latter, Europe has more to gain than to lose from Turkeys membership which would strengthen the countrys ties to the West, and provide a chance of proving to the world that the motto of the European Union united in diversity is a better model for the future of international relations than the scenario of a clash of civilizations. --

The inequality of electoral participation in Europe and America and the politically integrative functions of the welfare state

Electoral turnout is shown to be higher and less socially skewed in member states of the enlarged European Union than in the United States. The differences in the levels of turnout can partly be related to differences in election procedures, but since the procedural rules provide similar incentives or disincentives to all social groups they cannot explain the much higher inequality of electoral participation in America. There is some evidence to sustain the notion that the higher inclusiveness of the West European welfare state fosters political integration and the equality of electoral participation. In line with this notion differences between Europe and America diminish considerably when the analysis is confined to the pensioner generation whose integration into welfare state schemes is largely similar on both sides of the Atlantic. --