Browsing by Type "Habilitation"

Human rights, democracy and development have been understood as different themes and handled accordingly. Since the Vienna Human Rights Conference of 1993 and the discussions on Rights Based Approaches in recent years, the separation is increasingly questioned and development cooperation has asked for and promoted approaches which combine human rights, democratization and (economic) development. Based on comprehensive and multidisciplinary theoretical clarifications (chapter 2) the present work presents the thesis that human rights, democracy and development are complementary and mutually reinforcing ("all good things go together"). This is important in two regards. First, new areas and horizons are opening up for political science (especially for human rights-based democratization theory and policy analysis in developing countries and development cooperation). Second, development cooperation should encourage and promote the development and implementation of a human rights and democratization approach. Given the difficult framework conditions (a suboptimal international system of human rights protection, non-existence of a global government system etc.) (chapter 3), it is important to tackle the traditional challenges with innovative approaches. In chapter 4, several empirically researched challenges and approaches from various developing countries (mainly from Rwanda, Cambodia and South Africa) are presented and discussed. It appears that much needs to be done and much can be done on the ground. Human rights are helpful to tackle these challenges as they provide an important reference system. Human rights can be operationalized by using the triad of obligations (to respect, to protect, to fulfil), which allows to specify state obligations at three levels (chapter 5). Furthermore, the analysis of experiences that various actors have already made in promoting human rights and democracy (chapter 6) helps to identify precise results at the normative, analytical and operational levels, which are presented in chapter 7. Beside the big challenge of a (new) global governance system, the challenge is now to combine more closely human rights, democracy and development in theory and in practice, so that a virtuous cycle gets under way (chapter 8).

The thesis consists of eight articles that have been published recently in various scientific journals. It contains contributions to the theory and statistics of max-stable processes including their representation (Chapter 2), likelihood-based inference (Chapter 3), unconditional simulation (Chapters 4, 5 and 6) and conditional simulation with applications to downscaling and statistical post-processing (Chapters 7. 8 and 9). Brief overviews over the main results in these areas and the author's contributions will be given in an introductory chapter.

We give a comprehensive treatment of the area known as constructive reverse mathematics, which aims to classify, over intuitionistic logic, various theorems in intuitionistic, constructive recursive, and classical mathematics. Our work provides an overview of many known results, but also many new results, and new proofs of known results. We cover omniscience principles, Markov’s principle, Brouwer’s fan theorem(s), recursive principles, Ishihara’s boundedness principle BD-N, as well as minor principles, and separation techniques.

Objekt-orientierte Programmiersprachen ausgestattet mit Vererbungsmechanismen unterstützen vor allem schnelle Prototypentwicklung von Programmen und haben einen hohen Grad an Wiederverwendbarkeit von existierenden Ressourcen. Einen kritischen Punkt der objekt-orientierten Programmiersprachen stellt ihre Implementierung dar. Abgesehen von erheblichem Speicherplatzbedarf eines objekt-orientierten Systems kämpfen Programme dieser Sprachen im Gegensatz zu gleichbedeutenden C/C++-Programmen mit ihrer "problematischen" Laufzeiteffizienz. Daher spielen Optimierungstechniken für objekt-orientierte Sprachen zur Steigerung der Effizienz eine übergeordnete Rolle. Die vorliegende Arbeit beschäftigt sich mit einem Modell zur statischen Analyse von ungetypten objekt-orientierten Programmen. Die behandelte Programmiersprache ist eine Smalltalk-80-artige Sprache.

Continuum mechanics is nowadays widely used to describe the material behavior of systems, which occupies a specific area in space. In contrast to atomistic and molecular models, which can be solved using molecular dynamics or Monte-Carlo simulations, we consider the system to exist as a continuum. Due to their different material behavior we distinguish between solid mechanics and fluid mechanics. The typical deformation of the former one allows us to follow the movement of each particle in space, whereas we can not do this for the latter one. This leads to different formulations, which will be presented here. Typically, we want to achieve a solution for the balance of linear momentum for the continuum mechanical system. Additionally, we will derive a pure mass transport problem to demonstrate the capabilities of the numerical framework we have developed to solve these kind of problems. Once we have introduced the continuum mechanical framework, we can extent this to include further physical effects. Moreover, we extent the solid mechanical system to include thermal contributions and apply an additional pressure field to enforce the incompressibility of the fluids in the case of low Mach numbers. Within the continuous setting, we can define various interfaces. Internal interfaces can be used to decompose bodies into different subsets, e.g. to define areas with different physical properties or, on a more technical level, to enable parallelization on modern cluster architectures. External interfaces on solids can be used to include contact between multiple bodies. Additionally we could establish an interface at the external boundary to transfer momentum between a solid and the surrounding fluid. To avoid technical problems in the case of large deformations of solids, embedded within a fluid, we employ continuum immersed strategies to include the effects of fluid-structure interaction. Finally, we want to use phase field models for the simulation of phase separation and coarsening in solder alloys. We obtain sharp interfaces between the phases using the well known Cahn-Hilliard model to represent the free energy of the phases as well as of the interface. Similar to the immersed strategies, we aim at the simulation of the whole domain, avoiding the explicit representation of interfaces. To solve the arising initial boundary value problem in space, we first apply the finite element method for all problems at hand. In particular, we introduce Lagrangian as well as NURBS based shape functions for the underlying approximation of the field equations, written in weak form. Furthermore, we show how to incorporate discrete interface models in an optimal sense with regard to the consistency error at the interface using the Mortar method. The application of Mortar methods to NURBS will be shown as well. Due to the higher continuity requirement of the Cahn-Hilliard equation, the use of NURBS seems to be natural for this kind of problems. Since we deal with initial boundary value problems, suitable time integration schemes have to be developed as well. In general, we use a common implicit integration scheme for all problems at hand, such that we could use various fields simultaneously in a consistent framework. If possible, we aim at the development of structure preserving integrators, since they provide enhanced numerical stability for large time steps. For the explicit interface representation we apply additional augmentation techniques to simplify the algebraic constraints and verify the underlying conservation properties.

This study delves into the dynamic transformation of human agency within the complex context of settlement-oriented immigration. It places a central focus on agency, examining it from interdisciplinary, structural, and non-structural perspectives while considering the individual and collective experiences throughout the migration process. The study employs a transnational lens and an interpretive approach, firmly grounded in the rigorous methodology of Grounded Theory. Using a versatile multimethod open research design, the research culminates in the development of an empirically grounded Immigrant Agency Theory. Through the migration and settlement lens, this theory engages the simultaneity hypothesis, bridging the realms of integration and transnationalism. Immigrant agency, derived from the empirical study, is conceptualized as a multifaceted analytical tool encompassing representational aspects (identity formations and frameworks), expressive dimensions (language use, the acquisition of voice, and multilingual practices), and operational facets (social actions). The Immigrant Agency Theory takes shape through an in-depth case study of immigrants from the former Soviet Union who embarked on their journey to Germany during the 1990s and early 2000s, representing the fourth wave of the East-West European migration in the 20th century. To illustrate the dynamics within the researched immigrant communities, the application of the transition and postcolonial frames additionally prove useful in explaining the dominance of the Russian language and the outcomes of cultural Sovietization/ Russification for the communities abroad. The thesis introduces novel insights by differentiating between identity formations and identity frameworks, illustrated through a semantic assessment of ‘russaki,’ an identity framework originating from the German context. Moreover, the thesis provides a comprehensive analysis of the processual character of language use as languaging, encompassing practices like translanguaging between German and Russian and examining the contexts in which such practices are prevalent. Then it offers an in-depth examination of social actions across the spheres of business and leisure within the immigrant communities under investigation. These findings illuminate the roles of language use, encompassing multilingualism and translanguaging, along with identity formations and frameworks, as well as entrepreneurial and leisure actions. These elements serve as mechanisms facilitating transition, engagement, resistance, and the expression of flexible ethnic boundarymaking, cultural pluralism, and the maintenance of difference through auto-exoticism as exemplified by the studied population groups. The study’s limitations primarily relate to its focus on first-generation immigrants. Furthermore, there are chronological constraints tied to migration enabled by the disintegration of the Soviet Union, which has affected the temporal scope of the research. Additionally, there is reduced analysis of the role of state and international agencies. The study specifically concentrates on individuals affiliated with Russian-speaking communities in Germany. Furthermore, the empirical study took place before the full-scale Russian invasion in Ukraine in 2022, a critical event that dramatically impacted the dynamics within the studied subjects on the ground. These limitations should be considered when interpreting the findings and their applicability to broader immigrant populations and different migration contexts. In conclusion, the study holds implications for the development of a comprehensive theory of immigrant agency that encompasses both individual and collective dimensions. It thoughtfully navigates structural and non-structural factors within transnational social and urban spaces. This research contributes significantly to the field of East-West European migration studies by adopting transition and postcolonial perspectives, allowing for a wide-ranging understanding of individual and collective experiences during migration amid the complex backdrop of social, political, and economic transformations.

This paper is concerned with the energy consistent simulation of motions of a viscoelastic continuum body, under inclusion of the coupling of thermal and mechanical fields. The corresponding algorithm is based on a four-field formulation in the Lagrangian description, in which the deformation mapping, the velocity field, the temperature field and a strain-like viscous internal variable field are independent unknowns. Hence, the equations of motion are formulated in first-order form. The Lagrangian temperature field is determined by the first-order entropy evolution equation, associated with Fourier's law of heat conduction. The first-order viscous evolution equation is derived from an internal dissipation being quadratic in a nonlinear viscous strain-rate tensor. This coupled system of nonlinear differential equations is discretised by a new space-time finite element method, consisting of continuous as well as discontinuous finite element approximations in time. Owing to particular time approximations in the constitutive laws, beside the total linear momentum as well as the total angular momentum balance, a nonlinear stability estimate with respect to a relative energy function is exactly fulfilled in the fully discrete case as well. Hence, the resulting time integration algorithm is long-time nonlinear stable also when changing the time step size. The obtained coupled system of nonlinear algebraic equations is solved by a monolithic solution strategy. The corresponding Newton-Raphson methods on the global and the element level are based on a consistent linearisation. The new convergence criteria used for these iterative solution procedures take the energy consistency into account, and is free of the scaling in the independent variables. Representative numerical simulations with various boundary conditions show the higher-order accuracy and the superior stability of the new time integration algorithm.

The present thesis consists of three parts and accumulates a total of twelve scientific articles. The first part contains work that is related to the quark flavour sector of the Standard Model of particle physics. It contains papers from two sub-areas of this field of research: rare and radiative decays of B mesons, as well as non-leptonic decays of B mesons. Representatives of the former type are inclusive transitions of a bottom quark into a strange quark. These processes typically have tiny branching ratios and are therefore sensitive to contributions from particles beyond the Standard Model. Precise predictions from theoretical physics are required and are obtained by computing and including higher-order corrections (so-called loop corrections) in the perturbative expansion of the underlying quantum field theory, most prominently quantum chromodynamics (QCD) and quantum electrodynamics (QED). We evaluate loop corrections to two particular bottom-to-strange decays and provide updated theory predictions to many physical observables. Non-leptonic decays of B mesons on the other hand are of particular interest because they are sensitive to the phenomenon of CP violation. After including higher-order QCD corrections we give predictions for direct CP asymmetries to numerous decay channels in the framework of QCD factorisation. The second part deals with higher-order corrections in perturbative (QCD) to two particular quantities which have numerous applications in collider physics, namely the quark and gluon form factors. These form factors are the simplest objects containing infrared divergences at higher orders in massless quantum field theory, and therefore are of particular interest in many respects. They appear, for instance, as virtual higher-order corrections in coefficient functions for the inclusive Drell-Yan process, in deep-inelastic scattering, and in the inclusive Higgs production cross section. The quark and gluon form factors are evaluated analytically to three-loop accuracy in QCD. All terms to perform renormalisation at the four-loop level are also provided. Finally, the third part of the thesis is devoted to multi-loop calculations in supersymmetric gauge theories, in particular N=4 super Yang-Mills (SYM) theory. The quantities that we consider here are the Sudakov form factor and the angle-dependent cusp anomalous dimension. The Sudakov form factor is constructed to three-loop order from unitarity cuts, and assumes a particularly simple form if a suitable integral basis (called homogeneous basis) is chosen. Moreover, an interesting connection to the QCD quark and gluon form factors (see second part of the thesis) is revealed, which is called the leading transcendentality principle. The angle-dependent cusp anomalous dimension is first investigated in a particular limit, the scaling limit, in which ladder diagrams dominate. We give an algorithm to compute the solution in this limit at any loop order, and give explicit results to six loops. Next, we compute the complete planar (i.e. leading in colour) contribution to the angle-dependent cusp anomalous dimension at four loops in N=4 SYM theory, and the non-planar (sub-leading in colour) contribution in the aforementioned scaling limit.

Das Erkenntnisziel der vorliegenden Untersuchung ist, die lutherische Theologie des 20.Jahrhunderts zu verstehen. Diese schien sich von der Theologie Luthers, auf den sie sich immer berief, weit entfernt zu haben, prägte aber dennoch weitgehend das Lutherverständnis. Man stößt mit dieser Frage bald auf die großen Transformationen des 19.Jahrhunderts. Das bedeutet für die lutherische Theologie, dass man der Theologischen Fakultät der Erlanger Universität begegnet. Hier war mit gezielten homogenen Berufungen innerhalb von 15 Jahren ein Kreis bedeutender Gelehrter zusammen gekommen, der das kreative Zentrum der lutherischen Theologie bildete. Statt ausführlicher Erklärungen mag ein schlichter Hinweis die Erlanger Situation beleuchten. In der 2. Hälfte des 19.Jahrhunderts studierten mehr als die Hälfte der Erlanger Studierenden Theologie. Sie kamen von überall her. Auch wenn die Universität Erlangen damals eine zwar moderne, aber kleine Universität war, ist es singulär, dass sie ihre Bedeutung vor allem dem Ansehen ihrer Theologischen Fakultät und deren Studierenden verdankte. Die Untersuchung führt zu zwei grundlegenden Ergebnissen. Zunächst wird herausgearbeitet, dass das Geschichtsverständnis, das sich im 19.Jahrhundert herausbildete, in die Theologie aufgenommen wurde. Dabei fällt Schellings Religionsphilosophie eine vermittelnde Funktion zu. Zum anderen erhält das Verständnis der Kirche eine zentrale und integrierende Funktion in der gesamten Dogmatik. Die Kirche als die gegenwärtig in ihrer Zeit lebende konkrete Gemeinschaft der Menschen, die durch ihren Glauben verbunden sind, ist das Subjekt ihrer Geschichte. Ihre "Form" wandelt sich mit dem Verlauf ihrer Geschichte, sie bleibt aber in ihrem "Wesen" bei allen Veränderungen mit sich selbst identisch. Diese grundlegenden Ergebnisse dienen als heuristische Prinzipien zur Entfaltung der Erlanger Theologie in ihrer Systematik im Einzelnen sowie zur Darstellung der besonders markanten Konzeptionen ausgewählter Gelehrter. Es mag sein, dass die Entfaltung der Erlanger Theologie in die Breite der sie tragenden Persönlichkeiten und ihrer Themen mehr zu deren Verständnis beiträgt als die grundlegenden Thesen selbst. Im 21.Jahrhundert ist erneut eine Interesse an der Theologie des 19.Jahrhunderts entstanden. Ein Motiv ist offensichtlich, dass die Relevanz eines theologisch reflektierten Geschichts- und Kirchenverständnisses wieder entdeckt wurde. Jetzt setzt die Fragestellung eine andere Selbstwahrnehmung voraus. Man befindet sich in der Situation unübersehbar vielfältiger Gestaltungen christlicher Gemeinschaften, die durch ihre jeweilige Geschichte bedingt sind, und sucht nach dem wesentlich Gemeinsamen.