Die Deutung des Energie-Impuls-Tensors des Dirac-Feldes

By comparing the structure of the particle current and of the energy and momentum density, the meaning of the various tensor components is clarified. We decompose the energy momentum tensor into two parts. The one describes orbital, the other spin properties.     

Zur Wahl des Energie-Impuls-Tensors des Klein-Gordon-Feldes

The interpretation of the Klein Gordon tensor as energy momentum tensor turns out to be physically inconsistent. Therefore we propose a different tensor.     

Le langage des espaces et des groupes quantiques

We study the foundations of the differential calculus in quantum geometry. The notions of (differential) quantum space and cone are introduced. Generalizing a construction of Manin, to a quantum cone we associate the quantum group of its linear automorphisms preserving the differentials and deduce a de Rham complex on this group. We give examples of differential calculi on quantum hyperplanes and quantum linear groups.     

Modellierung des Energieaustausches in den Gleichungen des turbulenten Spannungstensors

Modelling of Pressure-strain Correlation in Reynolds Stress Equations From the structure of similarity of Reynolds stresses in homogeneous shear flow we derive the formula of pressure-strain-correlation.