Stochastic density fluctuations in the radiation era of the Universe

The linear stochastic hydrodynamical equations of the radiation-matter-one-component fluid in the Universe before the recombination era are solved. The stochastic forces in the heat flux and the viscous stress tensor are described according the procedure of Landau and Lifshitz. In the case of a low density universe, where the effects of the thermal conductivity can be neglected with respect to the shear viscosity, we find analytical solutions of the dispersion relation for the different modes and of the density correlation function . At the very Jeans length, this density correlation function exhibits a linear (for very large times) or a cubic (for small times) time dependence instead of a frozen-in character of this special mode.     

Hochtemperatur-Plagioklas im Meteorit von Oldenburg

Zusammenfassung Der Plagioklas im Meteorit von Oldenburg (10. 9. 1930) zeigt Hochtemperaturoptik, die damit auch für weitere Chondrite wahrscheinlich ist. Zusammensetzung ist An₁₁, 2V = 60 1/2°, = 1,5365, Auslöschungsschiefe 7 1/2°, Winkel zwischen und der 0-Stelle der Auslöschung 24°, Winkel zwischen [001] und = 20°. Anteil 6%, Verzwillingung sehr eng nach dem Albit- und Periklingesetz. Die Indikatrix wird mit den bisherigen Werten für die Hochtemperaturoptik verglichen.     

Spektralanalyse sehr kleiner meteoritischer Kügelchen

Zusammenfassung Die spektralanalytisch untersuchten Kügelchen der Tiefsee sind durch ihren Nickelgehalt als meteoritisch ausgewiesen.Bei den meisten Funden aus Bohrkernen muß eine technische Entstehung vor allem bei höheren Mangangehalten vermutet werden, so daß von einer Art Uhr, die die Sedimentationsgeschwindigkeit anzeigt, noch nicht gesprochen werden kann.Herrn Professor Dr. Dr. h. c.C. W. Correns zum 70. Geburtstag gewidmet.     

Structural evolution of the contact between two Penninic nappes (Zermatt-Saas zone and Combin zone,Western Alps) and implications for the exhumation mechanism and palaeogeography

The boundary zone between two Penninic nappes, the eclogite-facies to ultrahigh-pressure Zermatt-Saas zone in the footwall and the blueschist-facies Combin zone in the hanging wall, has been interpreted previously as a major normal fault reflecting synorogenic crustal extension. Quartz textures of mylonites from this fault were measured using neutron diffraction. Together with structural field observations, the data allow a refined reconstruction of the kinematic evolution of the Pennine nappes. The main results are: (1) the contact is not a normal fault but a major thrust towards northwest which was only later overprinted by southeast-directed normal faulting; (2) exhumation of the footwall rocks did not occur during crustal extension but during crustal shortening; (3) the Sesia-Dent Blanche nappe system originated from a continental fragment (Cervinia) in the Alpine Tethys ocean, and the Combin zone ophiolites from the ocean basin southeast of Cervinia; (4) out-of-sequence thrusting played a major role in the tectonic evolution of the Penninic nappes. An erratum to this article can be found at     

A direct hydrodynamical approach to the evolution of the density correlations in an expanding flat Friedmann Universe

A direct approach of the dynamical equation for the evolution of the two-point density correlation function is given in an expanding flat Friedmann Universe in the Newtonian approximation. If the third and higher moments are neglected, a wave-like equation of third-order for the two-point density correlation function is found. The exact solution of this equation shows, in the large time limit, the usual Jeans instability t ^4/3. It is suggested that the highern-point correlation function of the density grow liket ^2n/3 in the same approximation. This indicates that every truncation procedure of the hierarchy of the equations is inapplicable at least for large timest.