Magnetic dipole excitations in nuclei: elementary modes of nucleonic motion

The nucleus is one of the most multi-faceted many-body systems in the universe. It exhibits a multitude of responses depending on the way one 'probes' it. With increasing technical advancements of beams at the various accelerators and of detection systems the nucleus has, over and over again, surprised us by expressing always new ways of 'organized' structures and layers of complexity. Nuclear magnetism is one of those fascinating faces of the atomic nucleus we discuss in the present review. We shall not just limit ourselves to presenting the by now very large data set that has been obtained in the last two decades using various probes, electromagnetic and hadronic alike and that presents ample evidence for a low-lying orbital scissors mode around 3 MeV, albeit fragmented over an energy interval of the order of 1.5 MeV, and higher-lying spin-flip strength in the energy region 5 - 9 MeV in deformed nuclei, nor to the presently discovered evidence for low-lying proton-neutron isovector quadrupole excitations in spherical nuclei. To the contrary, we put the experimental evidence in the perspectives of understanding the atomic nucleus and its various structures of well-organized modes of motion and thus enlarge our discussion to more general fermion and bosonic many-body systems.Comment: 59 pages, 59 figures, accepted for publication in Rev. Mod. Phys

Book review: radicalized: new jihadists and the threat to the West by Peter R. Neumann

In Radicalized: New Jihadists and the Threat to the West, Peter R. Neumann explores the phenomenon of the ‘new jihadists’ travelling from the West to join and/or train with ‘Islamic State’ and reflects on the scale of the threat this poses to Western nations. While more on the role of women within the movement and analysis of a wider range of European examples would have been welcome, this meticulously researched and engagingly written book is highly recommended by Jennifer Philippa Eggert

Early food production in the Sahel of Burkina Faso

This paper is concerned with the transition from hunting and gathering to food production in West Africa, based on evidence from the Sahel Zone of Burkina Faso compiled by field research during the last years. Our study intends to enhance the knowledge about the West African versions of this transition, traditionally seen as one of the most fundamental changes in human prehistory. Embedded in an interregional program the Sahel Zone of Burkina Faso has proved to be one of its most unexpected examples

Whither Pentecostal Experience?: Mediated Experience of God in Pentecostal Theology

Experience of God (the Holy Spirit) has always been an integral part of Pentecostal theology and spirituality. Traditionally such experience has been considered rather direct or immediate, and as such has functioned as an authority for Pentecostals. More recent developments within Pentecostal theology, however, demonstrate that a more nuanced, mediated view of experience of God is being employed by some Pentecostal theologians in an attempt to acknowledge the cultural and linguistic embeddedness of all appeals to experience. Evidence of this mediated view of experience is exhibited in the work of Simon K. H. Chan, Frank D. Macchia, and Amos Yong, and has enabled creative ways forward for Pentecostal theology

Zum Konzept der flüssigen Materie um 1750 am Beispiel Christian Wolffs

In meinem Beitrag geht es um die Frage, wie die platonischen-neuplatonischen und frühneuzeitlichen Vorstellungen eines Ätherleibs, der medizinischen spiritus-Theorie und deskosmischen Äthers im 18. Jahrhundert transformiert wurden. Im Vordergrund steht die an Leibniz’ Philosophie angelehnte Materietheorie Christian Wolffs, der u. a. neuere neurophysiologische Erkenntnisse, aber auch alchemische Traditionen und Mutmaßungen zur Frage der elektrischen Materie in sein Konzept der flüssigen Materie integriert hat. Der Begriff der flüssigen Materie fungiert als Oberbegriff, der alle schnellen, volatilen und subtilen Materien unter sich fasst. Dazu gehören auch der Äther und das Nervenfluidum

Bootstrap tests for simple structures in nonparametric time series regression.

This paper concerns statistical tests for simple structures such as parametric models, lower order models and additivity in a general nonparametric autoregression setting. We propose to use a modified L2-distance between the nonparametric estimator of regression function and its counterpart under null hypothesis as our test statistic which delimits the contribution from areas where data are sparse. The asymptotic properties of the test statistic are established, which indicates the test statistic is asymptotically equivalent to a quadratic form of innovations. A regression type resampling scheme (i.e. wild bootstrap) is adapted to estimate the distribution of this quadratic form. Further, we have shown that asymptotically this bootstrap distribution is indeed the distribution of the test statistics under null hypothesis. The proposed methodology has been illustrated by both simulation and application to German stock index data.