Causality violation and singularities

We show that singularities necessarily occur when a boundary of causality violating set exists in a space-time under the physically suitable assumptions except the global causality condition in the Hawking-Penrose singularity theorems. Instead of the global causality condition, we impose some restrictions on the causality violating sets to show the occurrence of singularities.Comment: 11 pages, latex, 2 eps figure

Terminologie in der Fachkommunikation

In diesem Beitrag wird anhand eines Beispiels für missverständliche Kommunikation in der Luftfahrt aufgewiesen, welchen Nutzen Terminologiearbeit im Hinblick auf eine klare und eindeutige Kommunikation stiften kann. Die Antwort auf die Frage, wie Studierende zu einer professionellen Kommunikation befähigt werden können, soll dabei lauten: Indem sie zunächst vom Nutzen von Terminologiearbeit überzeugt werden und indem ihnen anschliessend das dafür notwendige Wissen vermittelt wird

The Cuban educational system : entanglements, influences and transfers : report on a workshop held in Havana, April 19 and 20, 2017, organized by the Instituto de Historia de Cuba, Havana and the Department of Economic and Social History of the University of Vienna

It is common knowledge that the self-declared Socialist state that is Cuba has entered unchartered territories in education. There is little research, however, on the far-reaching international resonance of the Cuban educational system, with regard to relations with both the existing community of socialist states and with Asia, Africa and Latin America. On the 19th and 20th of April, 2017, a research workshop, ‘The Cuban Educational System: Entanglements, Influences and Transfers’, took place in Havana. Invitations to participate in this event were extended by the Cuban Institute of History (Instituto de Historia de Cuba) and the Austrian Science Funded research project ‘Experts in Development’ and ‘Socialist Aid in the era of global competition between political systems West and East’ (Project Leader: Berthold Unfried, Department of Economic and Social History, Vienna University).peer-reviewe

Existence, Regularity, and Properties of Generalized Apparent Horizons

We prove a conjecture of Tom Ilmanen's and Hubert Bray's regarding the existence of the outermost generalized apparent horizon in an initial data set and that it is outer area minimizing.Comment: 16 pages, thoroughly revised, no major changes, to appear in Comm. Math. Phy

Volksbegehren und Volksentscheid

Auf Landes- und Kommunalebene sind Volksbegehren und Volksentscheid inzwischen in allen 16 Ländern eröffnet. Die vorherigen Warnungen der Gegner haben sich als unberechtigt erwiesen. Es ist an der Zeit, Direkte Demokratie auch auf Bundesebene einzuführen. ..

The limit space of a Cauchy sequence of globally hyperbolic spacetimes

In this second paper, I construct a limit space of a Cauchy sequence of globally hyperbolic spacetimes. In the second section, I work gradually towards a construction of the limit space. I prove the limit space is unique up to isometry. I als show that, in general, the limit space has quite complicated causal behaviour. This work prepares the final paper in which I shall study in more detail properties of the limit space and the moduli space of (compact) globally hyperbolic spacetimes (cobordisms). As a fait divers, I give in this paper a suitable definition of dimension of a Lorentz space in agreement with the one given by Gromov in the Riemannian case.Comment: 31 pages, 5 figures, submitted to Classical and Quantum gravity, seriously improved presentatio