Offener Brief an seine Mitberger: Meine liebe Mitberger! Es passiren in unseren Tagen so viele Geschichten, was man früher nich hat erlebt ...

Welsch (Projektbearbeiter): Äußerung von Unmut angesichts der sukzessiven Einschränkung der erst im März errungenen Versammlungsfreiheit sowie des geheimen Abtransports von Waffen aus Berlin. Appell zur Wachsamkeit und Warnung vor einer bewaffneten Reaktion

Offener Brief an den gewesenen Ober-Borgemeister Krausnick: Gewesener Herr Oberborgemeister! Mit großem Erstaunen habe ich gelesen, daß Sie haben geschrieben an unseren hochedlen Magistrat ...

Welsch (Projektbearbeiter): Satirische Kommentierung der Absicht des am 20. März 1848 abgesetzten Berliner Oberbürgermeisters Krausnick, sein Amt wieder aufzunehmen: " ... was würden Sie sagen, wenn Louis Philipp schriebe an die Französische Stadtverordnete in Paris, er will wieder eintreten in seine Krone? Würden Sie nich sagen: Der Mensch is meschugge?"

Offener Brief an das Ministerium Auerswald: Hohes Ministerium Auerswald! Um Gottes willen verschrecken Sie sich nich, daß Isaac Moses Hersch an Ihnen schreibt ...

Welsch (Projektbearbeiter): Bemängelung der personellen Kontinuität in den aufeinanderfolgenden Kabinetten Camphausen und Auerswald (Finanzminister Hansemann) sowie der allzu raschen Stellung der Vertrauensfrage an die Preußische Nationalversammlung. Lob für die Anerkennung der Revolution

Metternich's Testament, oder dessen politische Prophezeiungen der nächsten Zukunft

In Fraktur

Das Jahr 1849 im Guckkasten : Humoreske

In Fraktur

I. M. Hersch's Briefe

In Fraktur. - In deutsch-jiddischer Sprache

Jakob Steinhardts Graphik

Hermann Weyl

Sprüche Schelomohs

Hermann Weyl

Koheleth : ein philosophischer Versuch

Hermann Weyl

Perez : (aus einem zur siebenten Wiederkehr seines Todestags gehaltenen Vortrag)

Hermann Weyl

Hoffnung und Vertrauen : Predigt wegen des Ausmarsches des vaterländischen Heeres, gehalten am 28. März 1813 in Gegenwart mehrerer freiwilligen Jäger jüdischen Glaubens in der grossen Synagoge zu Berlin

von Meyer Simon Weyl

Lebens- und Regierungsgeschichte Friedrich Wilhelm's III., Königs von Preußen

Hrsg. von L. Weyl

Petrology and origin of basalts at DSDP Hole 66-487

The volcanism of Central America, according to current theory (Pichler and Weyl, 1973; Stoiber and Carr, 1974; Hey, 1977), is related to the subduction of the Cocos Plate under the North American lithospheric plate and the melting of ocean crust material in the subduction zone (Green and Ringwood, 1968; Dickinson, 1970, Fitton, 1971). Since Cocos Plate subduction occurs at the rate of more than 7 cm/y. (Hey et al., 1977), basalts underlying upper Miocene sediments of the Middle America Trench outer slope, penetrated in Hole 487 (Fig. 1) during Leg 66 (Moore et al., 1979), should have formed far from their present position if current theory is accurate. Present manifestations of basaltic magmatism in adjacent areas of the Pacific derive from the axial part of the East Pacific Rise, the Galapagos spreading center, and transform fracture zones. The question arises: Are there analogs of the Middle America Trench basalts among magmatic cock associated with these modern features, or do the trench basalts have some other origin?

Topological invariance and spatial scaling of surface roughness in two highly eroded zones of Mexico: a comparative study

The Fractal Image Informatics toolbox (Oleschko et al., 2008 a; Torres-Argüelles et al., 2010) was applied to extract, classify and model the topological structure and dynamics of surface roughness in two highly eroded catchments of Mexico. Both areas are affected by gully erosion (Sidorchuk, 2005) and characterized by avalanche-like matter transport. Five contrasting morphological patterns were distinguished across the slope of the bare eroded surface of Faeozem (Queretaro State) while only one (apparently independent on the slope) roughness pattern was documented for Andosol (Michoacan State). We called these patterns ?the roughness clusters? and compared them in terms of metrizability, continuity, compactness, topological connectedness (global and local) and invariance, separability, and degree of ramification (Weyl, 1937). All mentioned topological measurands were correlated with the variance, skewness and kurtosis of the gray-level distribution of digital images. The morphology0 spatial dynamics of roughness clusters was measured and mapped with high precision in terms of fractal descriptors. The Hurst exponent was especially suitable to distinguish between the structure of ?turtle shell? and ?ramification? patterns (sediment producing zone A of the slope); as well as ?honeycomb? (sediment transport zone B) and ?dinosaur steps? and ?corals? (sediment deposition zone C) roughness clusters. Some other structural attributes of studied patterns were also statistically different and correlated with the variance, skewness and kurtosis of gray distribution of multiscale digital images. The scale invariance of classified roughness patterns was documented inside the range of five image resolutions. We conjectured that the geometrization of erosion patterns in terms of roughness clustering might benefit the most semi-quantitative models developed for erosion and sediment yield assessments (de Vente and Poesen, 2005).

Einstein-like geometric structures on surfaces

An AH (affine hypersurface) structure is a pair comprising a projective equivalence class of torsion-free connections and a conformal structure satisfying a compatibility condition which is automatic in two dimensions. They generalize Weyl structures, and a pair of AH structures is induced on a co-oriented non-degenerate immersed hypersurface in flat affine space. The author has defined for AH structures Einstein equations, which specialize on the one hand to the usual Einstein Weyl equations and, on the other hand, to the equations for affine hyperspheres. Here these equations are solved for Riemannian signature AH structures on compact orientable surfaces, the deformation spaces of solutions are described, and some aspects of the geometry of these structures are related. Every such structure is either Einstein Weyl (in the sense defined for surfaces by Calderbank) or is determined by a pair comprising a conformal structure and a cubic holomorphic differential, and so by a convex flat real projective structure. In the latter case it can be identified with a solution of the Abelian vortex equations on an appropriate power of the canonical bundle. On the cone over a surface of genus at least two carrying an Einstein AH structure there are Monge-Amp`ere metrics of Lorentzian and Riemannian signature and a Riemannian Einstein K"ahler affine metric. A mean curvature zero spacelike immersed Lagrangian submanifold of a para-K"ahler four-manifold with constant para-holomorphic sectional curvature inherits an Einstein AH structure, and this is used to deduce some restrictions on such immersions.