A new compound method to compute periodic orbits in symplectic maps without the use of symmetries is presented. The results corroborate classical results from renormalization theory in examples not considered in the literature. Moreover the findings suggest a natural procedure to compute critical self-similar geometrical coefficients for these new cases.

Die Global Open Knowledgebase (GOKb) ist eine Online-Plattform für die kooperative Verwaltung von Zugriffsinformationen zu E-Ressourcen. Das Konzept für den Aufbau und die Pflege der verzeichneten Daten basiert auf der Kordinierung und Verwaltung durch die Bibliotheken selbst, um mit dem dort vorhandenen Fachwissen eine qualitativ hochwertige, unabhängige und freie Quelle für nachgelagerte Systeme (ERM, Discovery etc.) anbieten zu können. Da die Lizenzierung von solchen Ressourcen (E-Books, E-Journals etc.) selten einzeln, sondern meist im Rahmen von...

The (classical) contact process is a stochastic process on the vertices of a graph, which is a discrete, spatial model for the spread of a disease. The state of the contact process at time t is given by an infected subset of the vertices of the graph. At rate 1, each infected vertex becomes healthy, and therefore susceptible to reinfection. At rate lambda>0, each edge between an infected vertex and a healthy vertex transmits the...

The Gauss circle problem consists in counting the number of integer points of bounded length in the plane. This problem is equivalent to counting the number of closed geodesics of bounded length on a flat two dimensional torus. Many counting problems in dynamical systems have been inspired by this problem. For 30 years, the experts try to understand the asymptotic behavior of closed geodesics in translation surfaces and periodic trajectories on rational billiards. (Polygonal billiards...

Kontsevich and Zorich famously classified the connected components of strata of translation surfaces over moduli space. The corresponding problem over the Teichmüller space requires the analysis of which mapping classes can be realized as deformations lying inside the stratum. In this talk, I will present joint work with Nick Salter in which we classify the (non-hyperelliptic) connected components of strata over Teichmüller space. Unlike the case for strata over moduli space, we find that there...

Wir stellen hier das Graswurzel-Netzwerk "Tutorials in Bibliotheken" vor, welches sich im März 2021 gegründet hat. Ziel unserer Community ist es, in Bibliotheken tätige Menschen zu vernetzen, die Tutorials bereits erstellen bzw. sich für deren Erstellung interessieren. Die Themen umfassen den vollständigen Zyklus von Planung, Erstellung, Verbreitung und Evaluation von Tutorials. Konkret werden z.B. Konzepte, Didaktik, Programme/Plattformen, technisches Zubehör, Veröffentlichung und Verbreitung besprochen. Neben dem Wissenstransfer innerhalb der Community öffnet sich das Netzwerk auch nach...

Clythia sp. (Cnidaria, Hydrozoa, Hydroidomedusae, Leptomedusae, Campanulariidae), diameter 550 µm, Sylt 10.2015. 1:23 min. Medusa with short manubrium, four marginal bulbs, hollow tencacles, statocyst in between. Video can be used for teaching.

Mit 25.000 Wissenschaftlern und Ingenieuren, die ein jährliches Forschungsbudget von insgesamt 2,3 Milliarden Euro erhalten, ist Fraunhofer Europas größte Forschungs- und Technologieorganisation (RTO), die angewandte Forschung betreibt, die die wirtschaftliche Entwicklung vorantreibt und dem allgemeinen Wohl der Gesellschaft dient. Mit 72 einzelnen Instituten und Forschungseinheiten führt Fraunhofer Forschungsprojekte an Standorten im In- und Ausland durch. Seit 2016 steht das Competence Center Research Services & Open Science, als Fraunhofer-interner Dienstleister für die Publikationsinfrastruktur bei Fraunhofer, vor...

I will present an index associated to a local unitary and a projection in the setting of many-body interacting particles on a lattice. Its values are in general rational, being integer multiples of the inverse of the rank of the projection.

The L-Space Conjecture is taking the low-dimensional topology community by storm. It aims to relate seemingly distinct Floer homological, algebraic, and geometric properties of a closed 3-manifold Y. In particular, it predicts a 3-manifold Y isn't "simple" from the perspective of Heegaard-Floer homology if and only if Y admits a taut foliation. The reverse implication was proved by Ozsvath and Szabo. In this talk, we'll present a new theorem supporting the forward implication. Namely, we'll...

Phaeocystis globosa (Prymnesiophytes, Phaeocystaceae), diameter 480 µm, Sylt 10.2015. 0:20 min. Phaeocystis globosa is the most important species of Prymnesiophytes in the North Sea. This species occurs as single motile flagellate form and may also develop blooms (palmella form, colonies with a size up to some cm) which may influence development of bentic fish and other organisms because of anoxic conditions as a result of such blooms. Video can be used for teaching.

Odontella rhombus (Bacillariophyta, Coscinodicophyceae, Triceratiales, Triceratiaceae), length 120 µm, Sylt 10.2015. 0:35 min. Cells rhomboid in valve view, densely packed with chloroplasts, brownish colour, usually single cells. Video can be used for teaching.

Guinardia striata (=stolterfothii) (Bacillariophyta, Coscinodicophyceae, Rhizosoleniales, Rhizosoleniaceae), diameter 33 µm, Sylt 10.2015. Cylindrical and slightly curved cells, with flat valves, forming circular to spiralling chains. Valve face with spine and corresponding depression. Numerous chloroplasts. Nucleus central and near the cell wall. Video can be used for teaching.

Guinardia delicatula (Bacillariophyta, Coscinodicophyceae, Rhizosoleniales, Rhizosoleniaceae), diameter 22 µm, Sylt 10.2015, 0:15 min. Cells cylindrical, with a delicate spine at the valve face and an according depression for the contrary spine, forming straight chains, some irregularly lobed chloroplasts with large pyrenoids. Video can be used for teaching.

Single chaeta (“Polychaeta) of an undetermined species, length 700 µm, Sylt 11.2014. 0:23 min. Chaeta are characteristic structures of polychaetes. They belong to more or less each segment and can be numerous and often specialized in different body regions. Video can be used for teaching.

Coscinodiscus radiatus (Bacillariophyta, Coscinodicophyceae, Coscinodiscales, Coscinodiscaceae), diameter 225 µm, Sylt 11.2014. 0:26 min. Valves wider than high, valve centre with rosette of larger areolae. Video can be used for teaching.

Cerataulina pelagica (Bacillariophyta, Coscinodiscophyceae, Hemiaulales, Hemiaulaceae), diameter 11 µm, Sylt 11.2014. 0:25 min. Cylindrical cells form long, strait chains, valve margins with two winged processes, by which the cells are connected. Video can be used for teaching.

Biddulphia alternans (Bacillariophyta, Coscinodiscophyceae, Biddulphiales, Biddulphiaceae), length 120 µm, Sylt 11.2014. 0:25 min. Often solitary cells, rectangular or triangular in valve view. Three costae separate areas in the three valve corners. Cells can be connected to irregular or zig-zag chains. Video can be used for teaching.