Luther’s Mysticism, Pietism, and Contemplative Spirituality

To ask, “Why church?” certainly stirs multilayered theological, missional, ecclesial, and pastoral reflection. The question also has spiritual ramifications. To explore some of them, we will trace a thread of the Lutheran spiritual tradition from Martin Luther’s own “faith mysticism” through particular aspects of German pietism. That overview will provide a foundation for engaging the contemporary contemplative movement, in order to discern how its concepts and practices might provide insight for the practice of spirituality. Our conviction is that deepening the interior journey through a living, active faith leads not to withdrawal but to an awareness—even a vulnerability—that welcomes a healthy struggle with the realities of our world

Evangelicals and Roman Catholic Spirituality

After almost twenty-five years of teaching at an evangelical seminary in the Pacific Northwest I am seeing an emerging interest in and hunger for Catholic spirituality and mysticism among many of our students, both at the master’s and doctor of ministry levels. It is exciting to see spirituality as a conduit for Roman Catholic – Evangelical ecumenism and dialogue

Collaboration and Conflict in Europe around the Early Tranquebar Mission

Some 300 years ago, on July 9,1706, a new epoch in Protestantism began when Bartholomew Ziegenbaig and Heinrich Plütschau landed as missionaries at Tranquebar on the eastern coast of southern India. This mission, though not as well known as later Moravian Brethren missionary efforts or William Carey’s momentous journey, must be regarded as the first on-going Protestant foreign mission work.^ The cooperative nature of this endeavor throughout much of the eighteenth century has frequently been noted^ and stands in stark contrast to the more insular character of missions in the nineteenth century. It is the story of how an Anglican voluntary society in England supported a Royal Danish Mission in the sending of Lutheran missionaries from the Pietist center of Halle to Tranquebar

Using Hybrid Effectively in Christian Higher Education

Hybrid is just one of a number of terms used for the convergence of face-to-face and online learning, At the University of Central Florida (UCF) they are called mixed mode courses, In the corporate world the most common language used for hybrid is blended learning, Blended learning, says Bob Mosher, is about using multiple learning modalities, which include, but are not limited to, the Web.7 The blended learning term is also being used more frequently within academic circles,8 Because of the inconsistency in how blended learning is employed, though, and because our goal is not to describe learning in general but to focus on individual courses, this article will use the term hybrid and will apply it more narrowly to mean a course in which face-to-face and online learning are integrated in such a way that the seat time of the course is reduced

A quick guide to defect orbifolds

We provide a lightning review of the construction of (generalised) orbifolds [arXiv:0909.5013, arXiv:1210.6363] of two-dimensional quantum field theories in terms of topological defects, along the lines of [arXiv:1307.3141]. This universal perspective has many applications, some of which we sketch in the examples of 2d Yang-Mills theory, Landau-Ginzburg models, and rational CFT.Comment: 11 pages, contribution to the String-Math 2013 proceeding

Fusion of Critical Defect Lines in the 2D Ising Model

Two defect lines separated by a distance delta look from much larger distances like a single defect. In the critical theory, when all scales are large compared to the cutoff scale, this fusion of defect lines is universal. We calculate the universal fusion rule in the critical 2D Ising model and show that it is given by the Verlinde algebra of primary fields, combined with group multiplication in O(1,1)/Z_2. Fusion is in general singular and requires the subtraction of a divergent Casimir energy.Comment: 17 page

A worldsheet extension of O(d,d;Z)

We study superconformal interfaces between N=(1,1) supersymmetric sigma models on tori, which preserve a u(1)^{2d} current algebra. Their fusion is non-singular and, using parallel transport on CFT deformation space, it can be reduced to fusion of defect lines in a single torus model. We show that the latter is described by a semi-group extension of O(d,d;Q), and that (on the level of Ramond charges) fusion of interfaces agrees with composition of associated geometric integral transformations. This generalizes the well-known fact that T-duality can be geometrically represented by Fourier-Mukai transformations. Interestingly, we find that the topological interfaces between torus models form the same semi-group upon fusion. We argue that this semi-group of orbifold equivalences can be regarded as the \alpha' deformation of the continuous O(d,d) symmetry of classical supergravity.Comment: 71 pages, 1 figure, minor additions and correction

The Stories Behind the Story (Foreword and Introduction to Introducing Evangelical Ecotheology: Foundations in Scripture, Theology, History, and Praxis)

Excerpt: Nathan and I (Dan) pulled into the Mbanhela community in the Gaza province of Mozambique and were greeted by the high-spirited singing of six women who form the livestock association of that small community. A Christian relief and development organization, of which Nathan is the country director, provided funds for a large chicken coop, feed, supplies, and 300 chickens for the Mbanhela community. In addition, it furnished training in basic animal husbandry and marketing. Every two months the community starts a new cycle with 320 chicks. Raising chickens for income empowers that community and helps it toward health and sustainability. But the goal of raising livestock is not just for community development. The Mbanhela community decided that God had called them to provide a home for twenty-nine orphans and other vulnerable children. (One woman, Pastor Ramira, said to us matter-of-factly, “God tells us to care for the orphans and widows, and so we do.”) Profits from the sale of the chickens help those children attend school and buy books and school supplies

An applied investigation of viscosity–density fluid sensors based on torsional resonators

Real-time viscosity and density measurements give insight into the status of many chemical and biochemical processes and allow for automated controls. In many applications, sensors that enable the real-time measurements of fluid properties use resonant elements. Such sensors measure induced changes in the element’s resonance frequency and damping that can be related to the fluid properties. These sensors have been widely researched, though they are not yet commonly used in industrial processes. This study investigates two resonant elements to measure the viscosity and density of Newtonian fluids. The first is a probe-style viscosity-density sensor, and the second is a non-intrusive tubular viscosity sensor. These two sensors were investigated using analytical, numerical, and experimental methods. In the analytical method, the sensors’ resonance frequencies and bandwidths were predicted based on reduced-order models for both structure and fluid. In the numerical method, the interaction of the resonant element with the fluid was investigated by means of computational fluid dynamics (CFD). Experiments were conducted for validation, to evaluate the sensors’ capabilities, and understand cross-sensitivity effects between viscosity and density. This work successfully modeled and validated the two different torsional resonant element sensors, namely the probe-style viscosity-density sensor and the tubular viscosity sensor against experiments. There are two key output parameters, i.e., resonance frequency and bandwidth. Using these parameters, it is possible to predict fluid viscosity and density. Overall, this work demonstrates the potential of numerical modeling for the development of torsional resonance sensors. These findings directly affect the development of the future generation of fluid viscosity and density sensors

Laser spectroscopy of coherent quantum states in single quantum dots.

Laser spectroscopy was used for studying single charge-tunable InAs quantum dots (QD). The spectroscopy system consisted of a high resolution microscope combined with a solid immersion lens, a grating spectrometer and an in-situ detector to study the homodyne signal of the resonant laser and the QD. Low density QD samples were fabricated, which allowed spectral isolation of individual QDs. A modulation technique was used for noise rejection. Resonant absorption spectroscopy was used for directly probing transitions between ground and excited QD states. Lineshapes and signal strength were linked to life and coherence times of QD states. A theoretical model was developed combining coherent and non coherent processes in a master equation. Positively and negatively doped sample structures enabled spectroscopy of negatively, neutral and positively charged excitons. The relaxation time of hole spin ground states in a single QD was probed using resonant excitation in a magnetic eld parallel to the growth direction. Optical selection rules enable control over hole spin orientation. Hole spin relaxation times were studied from zero to ve Tesla, with relaxation times of di erent QDs ranging from 200 s to 1 ms. No signi cant in uence of the external magnetic eld on the hole spin relaxation time was found. A hole spin initialisation delity close to 100 % was achieved. Readout of resonantly created QD states was realised via a new microscope system. This dark eld microscope utilised spatial and polarisation ltering techniques to suppress the excitation laser by up to six orders of magnitude. Both ltering devices were included in the standard microscope, making it a highly practical and versatile system. Collected QD emission exceeded the resonant laser background by a factor of 100 for an unsaturated X1 transition. Pump-probe spectroscopy of the 3-level biexciton system was carried out, with the back scattered signal collected in re ection allowing spectral ltering via a grating spectrometer. The recorded probe spectrum revealed Autler-Townes splittings for high pump laser intensities, demonstrating the coherent superposition of QD exciton states. Swapping the pump probe geometry revealed weak quantum interferences. Spectroscopy of hole spin ground states in an in-plane magnetic eld created a coherent superposition of hole spin ground states via a -system. The resulting quantum interference between hole spin states resulted in the creation of a dark state. This experiment is known in quantum optics as coherent population trapping. The extracted lower bound of the hole spin coherence time was 1 s with greater than 40 % probability, demonstrating the enormous potential of hole spins in QDs for quantum information processing as well as for quantum optical experiments