119 research outputs found
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
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
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
BPS Spectra and Non--Perturbative Couplings in N=2,4 Supersymmetric String Theories
We study the BPS spectrum in heterotic string compactifications,
with some emphasis on intermediate BPS states. These intermediate states,
which can become short in compactifications, are crucial for establishing
an exchange symmetry in compactifications. We discuss the
implications of a possible exchange symmetry for the BPS spectrum.
Then we present the exact result for the 1-loop corrections to gravitational
couplings in one of the heterotic models recently discussed by Harvey and
Moore. We conjecture this model to have an exchange symmetry. This
exchange symmetry can then be used to evaluate non-perturbative corrections to
gravitational couplings in some of the non-perturbative regions (chambers) in
this particular model and also in other heterotic models.Comment: 44 pages, LaTeX. Minor changes, version that will appear in Nucl.
Phys.
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
Trimethylsilyl tag for probing protein-ligand interactions by NMR
Protein-ligand titrations can readily be monitored with a trimethylsilyl (TMS) tag. Owing to the intensity, narrow line shape and unique chemical shift of a TMS group, dissociation constants can be determined from straightforward 1D 1H-NMR spectra not only in the fast but also in the slow exchange limit. The tag is easily attached to cysteine residues and a sensitive reporter of ligand binding also at sites where it does not interfere with ligand binding or catalytic efficiency of the target protein. Its utility is demonstrated for the Zika virus NS2B-NS3 protease and the human prolyl isomerase FK506 binding protein.C.N. and G.O. thank the Alexander von Humboldt Foundation for a
Feodor Lynen Fellowship and the Australian Research Council for a
Laureate Fellowship, respectively. Financial project support by the
Australian Research Council, the Austrian Science Fund (FWF) (DK
Molecular Enzymology W901 to K.Z.) and by NAWI Graz is gratefully
acknowledged
Instanton Numbers and Exchange Symmetries in Dual String Pairs
In this note, we comment on Calabi-Yau spaces with Hodge numbers
and . We focus on the Calabi-Yau space 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 dual models to six dimensional heterotic/heterotic
string duality.Comment: 16 pages, Latex, minor correction
Perturbative Couplings and Modular Forms in N=2 String Models with a Wilson Line
We consider a class of four parameter D=4, N=2 string models, namely
heterotic strings compactified on K3 times T2 together with their dual type II
partners on Calabi-Yau three-folds. With the help of generalized modular forms
(such as Siegel and Jacobi forms), we compute the perturbative prepotential and
the perturbative Wilsonian gravitational coupling F1 for each of the models in
this class. We check heterotic/type II duality for one of the models by
relating the modular forms in the heterotic description to the known instanton
numbers in the type II description. We comment on the relation of our results
to recent proposals for closely related models.Comment: 42 pages, LaTeX, revised version contains additional reference
- …