On the Duality between the Heterotic String and F-Theory in 8 Dimensions

In this note we compare the moduli spaces of the heterotic string compactified on a two-torus and F-Theory compactified on an elliptic K3 surface for the case of an unbroken E8 x E8 gauge group. The explicit map relating the deformation parameters alpha and beta of the F-Theory K3 surface to the moduli T and U of the heterotic torus is found using the close relationship between the K3 discriminant and the discriminant of the Calabi-Yau-threefold X(1,1,2,8,12)[24] in the limit of a large base P1.Comment: 10 pages, LaTe

Gustav Teichmüller and the Systematic Significance of Studying the History of Concepts

The history of concepts is relevant in philosophy because conceptual distinctions fundamentally shape cognition. Because these conceptual distinctions are deeply entrenched in our way of thinking, we are not usually aware of this influence. How we view the world depends crucially on the concepts we have. These concepts, however, are the products of their history. Following Herbart, Gustav Teichmüller viewed philosophy as the systematic analysis and refinement of concepts. Refining concepts in such a way allows us to make new distinctions, or to transform or abandon old ones. In contrast to Herbart, Teichmüller emphasized that this process presupposes detailed historical studies. This does not mean, however, that Teichmüller embraced a kind of historicism---the view that philosophy and its history are one and the same thing. On the contrary, he derogatorily referred to such a view as "historical psychology". Rather, the history of concepts in Teichmüller's sense has to be understood as a history of problems which are reflected in conceptual distinctions. This means that the history of concepts, which brings to light explicit and implicit distinctions, can be applied as a kind of hermeneutics of world views---as the basis on which we can systematically reconstruct concepts in a new light. It is the aim of this presentation to unfold such an understanding of the history of concepts in view of Teichmüller's contribution to it

The location of the primary entry tear in acute type B aortic dissection affects early outcome†

OBJECTIVES The goal of the retrospective study was to relate the site of the primary entry tear in acute type B aortic dissections to the presence or development of complications. METHODS A consecutive series of 52 patients referred with acute type B aortic dissection was analysed with regard to the location of the primary entry tear (convexity or concavity of the distal aortic arch) using the referral CT scans at the time of diagnosis. These findings were related to the clinical outcome as well as to the need for intervention. RESULTS Twenty-five patients (48%) had the primary entry tear located at the convexity of the distal aortic arch, whereas 27 patients (52%) had the primary entry tear located at the concavity of the distal aortic arch. Twenty per cent of patients with the primary entry tear at the convexity presented with or developed complications, whereas 89% had or developed complications with the primary entry tear at the concavity (P<0.001). Furthermore, in patients with complicated type B aortic dissection, the distance of the primary entry tear to the left subclavian artery was significantly shorter as in uncomplicated patients (8 vs. 21mm; P=0.002). In Cox regression analysis, a primary entry tear at the concavity of the distal aortic arch was identified as an independent predictor of the presence or the development of complicated type B aortic dissection. CONCLUSIONS A primary entry tear at the concavity of the aortic arch as well as a short distance between the primary entry tear and the left subclavian artery are frequently associated with the presence or the development of complicated acute type B aortic dissection. These findings shall help us to further differentiate acute type B aortic dissections in addition to the common categorization in complicated and uncomplicated. These findings may therefore also have an impact on primary treatmen

Analytical Philosophy and its Forgetfulness of the Continent. Gottfried Gabriel in conversation with Todor Polimenov

Gottfried Gabriel is interviewed by Todor Polimenov about the relationship between analytic and continental philosophy.Analytical Philosophy and its forgetfulness of the continent. Gottfried Gabriel in conversation with Todor Polimeno

Fact or Fiction?: The Problem of Historical Cognition

In Auseinandersetzung mit poststrukturalistischen Versuchen, die Unterscheidung zwischen Fakten und Fiktionen im Anschluß an Friedrich Nietzsche zu nivellieren, wird diese Unterscheidung mit Blick auf die Geschichtswissenschaft verteidigt. In begriffsgeschichtlicher Perspektive erfolgt sodann eine Diagnose panfiktionalistischer Tendenzen, die belegt, dass diese Tendenzen auf einer Vermischung von Fiktionalität mit Literarizität und Narrativität beruhen. Gegenüber zu einseitig szientifisch ausgerichteten methodologischen Bestrebungen in der Geschichtswissenschaft wird sodann die Relevanz der literarisch-narrativen Darstellungsform ins Spiel gebracht. Wenn dabei Gemeinsamkeiten zwischen Literatur und Geschichtsschreibung Beachtung finden, so gerade nicht, um die Historie in dekonstruktiver Absicht der fiktionalistischen ‚Mittäterschaft‘ zu verdächtigen, sondern ganz im Gegenteil, um das Erkenntnispotential der Literatur, das als narrative Vergegenwärtigungsleistung expliziert wird, für die historische Erkenntnis fruchtbar zu machen

El «escándalo de la filosofía». El problema de la realidad y su «disolución»

Not available.En las tradiciones más dispares de la filosofía de la praxis (desde Marx hasta Heidegger), el problema de la realidad y la contraposición entre el idealismo y el realismo epistemológicos que le va asociada constituyen la expresión de una relación alienada con el mundo. Dicho problema fue desechado con fundamentos muy distintos, pero con un resultado semejante, por representantes de la teoría de la ciencia (Carnap), quienes 10 consideraron un «problema aparente». Partiendo de los análisis de Schopenhauer y Wittgenstein sobre la temática de la alienación y el solipsismo, se tratará aquí no tanto de contraponer las posiciones del realismo y del idealismo como enunciados en conflicto, sino de conferirles el estatus de visiones del mundo que han de combinarse en cuanto aspectos complementarios de la humana conditio

Instanton Numbers and Exchange Symmetries in N=2N=2 Dual String Pairs

In this note, we comment on Calabi-Yau spaces with Hodge numbers $h_{1,1}=3$ and $h_{2,1}=243$. We focus on the Calabi-Yau space $WP_{1,1,2,8,12}(24)$ and show how some of its instanton numbers are related to coefficients of certain modular forms. We also comment on the relation of four dimensional exchange symmetries in certain $N=2$ dual models to six dimensional heterotic/heterotic string duality.Comment: 16 pages, Latex, minor correction