No Arabic abstract
Scientific research is and was at all times a transnational (global) activity. In this respect, it crosses several borders: national, cultural, and ideological. Even in times when physical borders separated the scientific community, scientists kept their minds open to the ideas created beyond the walls and tried to communicate despite all the obstacles. An example of such activities in the field of physics is the travel in the year 1838 of a group of three scientists through the Western Europe: Andreas Ettingshausen (professor at the University of Vienna), August Kunzek (professor at the University of Lviv) and P. Marian Koller (director of the observatory in Chremsminster, Upper Austria). 155 years later a vivid scientific exchange began between physicists from Austria and Ukraine, in particular, between the Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine in Lviv and the Institute for Theoretical Physics of Johannes Kepler University Linz. This became possible due to the programs financed by national institutions, but it had its scientific background in already knotted historic scientific networks, when Lviv was an international center of mathematics and in Vienna the School of Statistical Thought arose. Due to the new collaboration, after the breakup of the Soviet Union, Ukraine became the first country to join the Middle European Cooperation in Statistical Physics (MECO) founded in the early 1970s with the aim of bridging the gap between scientists from the Eastern and Western parts of Europe separated by the iron curtain.
With Cyrano, Voltaire, and Verne, France provided important milestones in the history of early science fiction. However, even if the genre was not very common a few centuries ago, there were numerous additional contributions by French-speaking writers. In this paper, we review two cases of interplanetary novels written in the second half of the eighteenth century and sharing a rare particularity: their authors were female. Voyages de Milord Ceton was imagined by Marie-Anne de Roumier-Robert whereas Cornelie Wouters de Wasse conceived Le Char Volant. While their personal lives were very different, and their writing style too, both authors share in these novels a common philosophy in which equality -- between ranks but also between genders -- takes an important place. Their works thus clearly fit into the context of the Enlightenment.
We investigate the impact of borders on the topology of spatially embedded networks. Indeed territorial subdivisions and geographical borders significantly hamper the geographical span of networks thus playing a key role in the formation of network communities. This is especially important in scientific and technological policy-making, highlighting the interplay between pressure for the internationalization to lead towards a global innovation system and the administrative borders imposed by the national and regional institutions. In this study we introduce an outreach index to quantify the impact of borders on the community structure and apply it to the case of the European and US patent co-inventors networks. We find that (a) the US connectivity decays as a power of distance, whereas we observe a faster exponential decay for Europe; (b) European network communities essentially correspond to nations and contiguous regions while US communities span multiple states across the whole country without any characteristic geographic scale. We confirm our findings by means of a set of simulations aimed at exploring the relationship between different patterns of cross-border community structures and the outreach index.
A short autobiography written for a centennial party.
The main focus of this paper is on models of quartic surfaces, especially so-called complex surfaces. These are special fourth-degree surfaces that Julius Plucker introduced in the 1860s for visualizing the local structure of a quadratic line complex. Pluckers complex surfaces turned out to be closely related to Kummer surfaces and both of these types of quartics are examples of caustic surfaces, which arise in geometrical optics. Indeed, Kummer surfaces represent a natural generalization of the wave surface, first introduced by Augustin Fresnel to explain double refraction in biaxial crystals.