Galois groups and connection matrices for -difference equations.
Choose with . The main theme of this paper is the study of linear -difference equations over the field of germs of meromorphic functions at . A systematic treatment of classification and moduli is developed. It turns out that a difference module over induces in a functorial way a vector bundle on the Tate curve that was known for modules with ”integer slopes“, [Saul, 2]). As a corollary one rediscovers Atiyah’s classification of the indecomposable vector bundles on the complex Tate...
This paper is concerned with extending Gehring theory to be applicable to Rothe's approximate solutions to hyperbolic differential equations.
Several ways to embed q-deformed versions of the Heisenberg algebra into the classical algebra itself are presented. By combination of those embeddings it becomes possible to transform between q-phase-space and q-oscillator realizations of the q-Heisenberg algebra. Using these embeddings the corresponding Schrödinger equation can be expressed by various difference equations. The solutions for two physically relevant cases are found and expressed as Stieltjes Wigert polynomials.
Im ersten Teil des Artikels konstruiert der Verfasser eine geschlossene Bewegung, die an der Ähnlichkeitsgruppe definiert wird. Solche Bewegungen beschreiben periodisch sich wiederholende Prozesse für den Fall des beweglichen Gebildes, welches sich während der Bewegung ähnlich deformiert. Der zweite Teil verallgemeinert die geschlossene Bewebungen durch äquiforme Bewegungen, die so gegeben werden, dass eine Folge von erzeugenden Punkten dieselbe Bahnkurve beschreibt in der Art, dass die einzelnen...
In this paper, we investigate the problem of global output-feedback regulation for a class of switched nonlinear systems with unknown linear growth condition and uncertain output function. Based on the backstepping method, an adaptive output-feedback controller is designed to guarantee that the state of the switched nonlinear system can be globally regulated to the origin while maintaining global boundedness of the resulting closed-loop switched system under arbitrary switchings. A numerical example...