Refine
Has Fulltext
- yes (71)
Year of publication
- 1997 (71) (remove)
Document Type
- Article (25)
- Preprint (25)
- Postprint (12)
- Monograph/Edited Volume (7)
- Part of Periodical (2)
Is part of the Bibliography
- no (71) (remove)
Keywords
- manifolds with singularities (3)
- pseudodifferential operators (3)
- Fredholm property (2)
- Mellin transform (2)
- conical singularities (2)
- elliptic operators (2)
- index (2)
- 'eta' invariant (1)
- APS problem (1)
- Atiyah-Bott condition (1)
Institute
- Extern (25)
- Institut für Mathematik (18)
- Zentrum für Umweltwissenschaften (17)
- Interdisziplinäres Zentrum für Dynamik komplexer Systeme (8)
- MenschenRechtsZentrum (7)
- Institut für Physik und Astronomie (6)
- Wirtschaftswissenschaften (4)
- Historisches Institut (3)
- Sozialwissenschaften (3)
- Department Erziehungswissenschaft (2)
We consider a G-invariant star-product algebra A on a symplectic manifold (M,ω) obtained by a canonical construction of deformation quantization. Under assumptions of the classical Marsden-Weinstein theorem we define a reduction of the algebra A with respect to the G-action. The reduced algebra turns out to be isomorphic to a canonical star-product algebra on the reduced phase space B. In other words, we show that the reduction commutes with the canonical G-invariant deformation quantization. A similar statement in the framework of geometric quantization is known as the Guillemin-Sternberg conjecture (by now completely proved).
We investigate the cognitive control in polyrhythmic hand movements as a model paradigm for bimanual coordination. Using a symbolic coding of the recorded time series, we demonstrate the existence of qualitative transitions induced by experimental manipulation of the tempo. A nonlinear model with delayed feedback control is proposed, which accounts for these dynamical transitions in terms of bifurcations resulting from variation of the external control parameter. Furthermore, it is shown that transitions can also be observed due to fluctuations in the timing control level. We conclude that the complexity of coordinated bimanual movements results from interactions between nonlinear control mechanisms with delayed feedback and stochastic timing components.
The attitude of the East Germans to the Polish is burdened with the heritage of the past. After 1945 the composition of the population on both sides of the new border along the Oder and Neisse rivers changed drastically. On the eastern side the Germans were expelled and Polish people were settled. On the western side many expelled Germans found a new home. Despite the fact that the GDR signed the Oder-Neisse border treaty, the ruling communist party (SED) did not encourage contacts between the people living on both sides of Oder and Neisse in the following years. The policy of the SED towards the Polish communists during the whole period between 1946-1989 was characterised by arrogance and suspicion, at times falling back on old anti-Polish stereotypes. Especially in the 1980s, the GDR tried to prevent the influence of Solidarnosc and dissident ideas from entering the country. Despite this policy, substantial personal contacts developed, particularly in the 1970s when the border was fully opened. The authors argue that current German-Polish relations should make use of these experiences.
The ill-posed problem of aerosol size distribution determination from a small number of backscatter and extinction measurements was solved successfully with a mollifier method which is advantageous since the ill-posed part is performed on exactly given quantities, the points r where n(r) is evaluated may be freely selected. A new twodimensional model for the troposphere is proposed.
In the rapidly growing literature on globalization, many authors have emphasized the apparent disembedding of social relations from their local-territorial preconditions. Such arguments neglect the relatively fixed and immobile forms of territorial organization upon which the current round of globalization is premised, such as urban-regional agglomerations and territorial states. Drawing on the work of David Harvey and Henri Lefebvre, this article argues that processes of reterritorialization - the reconfiguration of forms of terrritorial organization such as cities and states - must be viewed as an intrinsic moment of the current round of globalization. Globalization is conceived here as a reterritorialization of both socio-economic and political-institutional spaces that unfolds simultaneously upon multiple, superimposed geographical scales. The ongoing restructuring of contemporary urban spaces and state institutional-territorial structures must be viewed at once as presupposition, a medium and an outcome of this highly contested dynamic of global spatial restructuring. New theories and representations of the scaling of spatial practices are needed to grasp the rapidly changing territorial organization of world capitalism in the late 20th century.
We have studied the bifurcation structure of the incompressible two-dimensional Navier-Stokes equations with a special external forcing driving an array of 8×8 counterrotating vortices. The study has been motivated by recent experiments with thin layers of electrolytes showing, among other things, the formation of large-scale spatial patterns. As the strength of the forcing or the Reynolds number is raised the original stationary vortex array becomes unstable and a complex sequence of bifurcations is observed. The bifurcations lead to several periodic branches, torus and chaotic solutions, and other stationary solutions. Most remarkable is the appearance of solutions characterized by structures on spatial scales large compared to the scale of the forcing. We also characterize the different dynamic regimes by means of tracers injected into the fluid. Stretching rates and Hausdorff dimensions of convected line elements are calculated to quantify the mixing process. It turns out that for time-periodic velocity fields the mixing can be very effective.
Vor- und nacheiszeitliche Großtierformen in Mitteleuropa und ihre Einpassung in das Ökosystem
(1997)
Die Untersuchungen machen wahrscheinlich, daß ein Reichsministerialengeschlecht vor 1161 den Raum Treuenbrietzen okkupierte, dort einen Herrschaftssitz errichtete und mit einem ersten Landesausbau begann. Zwischen 1194 und 1208 endete die relative Selbständigkeit dieses Geschlechts. Brietzen wurde Bestandteil der erzbischöflich-magdeburgischen Territorialherrschaft Jüterbog, ging aber noch im 13. Jahrhundert in brandenburgisch-askanischen Besitz über.
It is shown that the Hankel transformation Hsub(v) acts in a class of weighted Sobolev spaces. Especially, the isometric mapping property of Hsub(v) which holds on L²(IRsub(+),rdr) is extended to spaces of arbitrary Sobolev order. The novelty in the approach consists in using techniques developed by B.-W. Schulze and others to treat the half-line Rsub(+) as a manifold with a conical singularity at r = 0. This is achieved by pointing out a connection between the Hankel transformation and the Mellin transformation.The procedure proposed leads at the same time to a short proof of the Hankel inversion formula. An application to the existence and higher regularity of solutions, including their asymptotics, to the 1-1-dimensional edge-degenerated wave equation is given.
Inhalt Leitartikel K. E. Grözinger: Zeichen des Umbruchs - Jüdische Studien in Deutschland Notizen Centrum Judaicum erwarb einmaliges Mendelssohn-Buch, Ludwig Geigers Bibliothek, Neue Jüdische Monatshefte, Stichwort: 100 Jahre Zionismus, Billige Bücher Kommentar Wahrheit und Politik Pressemitteilung Deutsches Holocaustmuseum, Aus der Forschung Freischul-Projekt Aus der jüdischen Welt, Verbandsnachrichten
Abschließende Bemerkungen des Menschenrechtsausschusses zum Bericht Deutschlands gemäß Art. 40 CCPR
(1997)
Filmfrauen - Zeitzeichen : Frauenbilder im Film der 40er, 60er und 90er Jahre ; Band II: Arbeiterin
(1997)
Die in den Heften 1-3 der „Potsdamer Studien zur Frauen- und Geschlechterforschung“ publizierten Beiträge sind Ergebnisse eines Projektes, das in den Jahren 1995 bis 1997 im Auftrag des Filmmuseums Potsdam am Lehrstuhl Frauenforschung an der Wirtschafts- und Sozialwissenschaftlichen Fakultät der Universität Potsdam realisiert wurde. Inhalt: England im Aufbruch. Alltagserfahrungen und ökonomische, soziale und kulturelle Rahmenbedingungen in England am Ende der 50er bis zum Anfang der 60er Jahre (Susan Geißler) Die VerliererInnen des Aufbruchs. Wie über AußenseiterInnen die (Geschlechter-)Normen der neuen britischen Mittelschichten diskursiviert werden. - Analyse des Films »Bitterer Honig« (Juliane Rödel) »Wir alle lieben Paula, aber uns liegt an Paul« - Wie über die ‘Weiblichkeit’ einer Arbeiterin der „sozialistische Mensch“ konstruiert wird. Analyse des Films »Die Legende von Paul und Paula« (Irene Dölling)
Filmfrauen - Zeitzeichen : Frauenbilder im Film der 40er, 60er und 90er Jahre ; Band III: Girlie
(1997)
Die in den Heften 1-3 der „Potsdamer Studien zur Frauen- und Geschlechterforschung“ publizierten Beiträge sind Ergebnisse eines Projektes, das in den Jahren 1995 bis 1997 im Auftrag des Filmmuseums Potsdam am Lehrstuhl Frauenforschung an der Wirtschafts- und Sozialwissenschaftlichen Fakultät der Universität Potsdam realisiert wurde. Inhalt: Paulas „Töchter“ on the road. Postmoderne ‘Weiblichkeit’ und sozialer Umbruch im Osten. Analyse des Films »Burning Life« (Irene Dölling) Tank Girl. Die Zähmung einer widerständigen Comicfigur Analyse des Films »Tank Girl« (Ina Dietzsch)