Dynamics of ferromagnetic nanomagnets with vortex or single-domain configuration

We study the dynamics of flat circular permalloy nanomagnets for 1.) magnetic vortex and 2.) single-domain configurations, using micromagnetic simulation. Dynamical studies for isolated vortex structures show that both the vorticity and the central polarity of the out-of-plane component can be switched fast (50-100 ps) and independently. Micromagnetic simulations of the switching process in thin cylindrical Permalloy (Py) nanoparticles with an initial stable single-domain state show nearly homogeneous single-domain behaviour followed by excitation of spin waves.Comment: 2 pages with 3 eps-figures, --> ICM2003 Rome 28.7.-1.8.03, --> JMM

Religiosity in the major religious cultures of the world

Compared to other cross-national surveys, the religion-modules of the International Social Survey Programme (ISSP) include a larger number of indicators on individual religiosity and thus allow for more differentiated analyses of cross-national differences. In this paper, we use these findings to point out in which ways the forms and development of religiosity differ between the major religious cultures of the world. In order to have a sufficient number of cases for all geographical macro-regions, three data sources were used: ISSP 2018 data from 37 countries, the 2018 Templeton survey that fielded ISSP 2018 survey questions in another 10 non-European countries, and data from the ISSP 2008 religion module for 10 countries that did not participate in ISSP 2018. The comparison covers three dimensions: religious affiliation and non-affiliation, private and public forms of religious practice, and different types of religious beliefs. In the final section, we discuss what conclusions can be drawn from the results with regard to the secularization thesis, i.e., the assumption that socioeconomic modernization leads to a decline in individual religiosity

Functional equivalence and validity of religiousness indicators in cross-cultural comparative surveys

Cross-cultural comparative surveys have become an important tool to investigate social attitudes across different countries. However, this methodology is confronted with a number of challenges. One of the core problems is the functional equivalence of the concepts and indicators used. In this article, we study this problem in regard to the investigation of religiousness in three prominent surveys, the World Value Survey, the International Social Survey Programme, and the Religion Monitor. Our contribution starts with the fundamental question of the intercultural meaning of single items that are commonly used for the measurement of religiosity. From the comparison of the linguistic formulation of these items in different languages and across the three surveys, we obtain evidence of whether the concept of religiousness has the same meaning in different countries and to what extent the results depend on the formulation of the item. Subsequently, we use confirmatory factor analysis to test whether two religiousness scales derived from the International Social Survey Programme are structurally equivalent across countries. In the final step, we proceed to a substantive analysis, comparing religiousness scales from the three surveys in order to examine to what extent scales that claim to measure the same construct in fact produce similar results when applied to different countries. Our findings suggest that the paradigm of "asking the same questions" is difficult to apply and problematical with respect to some core indicators of individual religiousness and that questionnaires that are based on the Western concept of religion will lead to biased results when applied to worldwide cross-cultural comparison

Influence of point defects on magnetic vortex structures

We employed micro-Hall magnetometry and micromagnetic simulations to investigate magnetic vortex pinning at single point defects in individual submicron-sized permalloy disks. Small ferromagnetic particles containing artificial point defects can be fabricated by using an image reversal electron beam lithography process. Corresponding micromagnetic calculations, modeling the defects within the disks as holes, give reasonable agreement between experimental and simulated pinning and depinning field values

Ursachen des Rückgangs der Religiosität in Europa

'Ausgangspunkt des Artikels ist der empirische Befund, dass der Verbreitungsgrad traditioneller Formen der Religiosität in verschiedenen Regionen der Welt, aber auch zwischen den Ländern Europas äußerst unterschiedlich ist. Es werden drei Faktoren erörtert, die für die Erklärung des Rückgangs der Religiosität in bestimmten europäischen Ländern von besonderer Bedeutung sind: 1. Die Reduzierung der Lebensrisiken durch die Verbesserung der materiellen Lebensbedingungen und den Ausbau des Wohlfahrtsstaats; 2. die Entzauberung der Religion vor allem durch den Protestantismus und der damit verbundene Verlust der sinnlichen Erfahrungsqualität der Religion; und 3. das konflikthafte Verhältnis zwischen Kirche und Bevölkerung im Verlauf der Geschichte, das dazu beigetragen hat, dass die Menschen nur wenig Vertrauen in die Kirche haben und sich heute in zunehmendem Maße von der Religion distanzieren.' (Autorenreferat)'Point of departure of this article is the empirical finding that the dissemination degree of traditional forms of religiousness varies strongly across different world regions, but also within Europe. Three factors are discussed, which are of particular importance for explaining declining religiousness in specific European countries. First, the reduction of risks to life as a consequence of the improvement of the material living conditions and the implementation of the welfare state; second, the demystification of religion, mainly because of European Protestantism, and the corresponding loss of sensual quality of religious experience; third, the frequently conflicting relationship between church(es) and the population during the course of history, which undermined the confidence in churches and has enhanced an increasing distancing from religion in our times.' (author's abstract)

On the significance of quantum effects and interactions for the apparent universality of Bloch laws for M_s(T)

The apparent universality of Bloch's T^{3/2}-law for the temperature dependence of the spontaneous magnetization, and of generalizations thereof, is considered. It is argued that in the derivation one should not only consider the exchange interaction between the spins, but also the other interactions between them, leading to elliptical spin precession and deviations from the parabolic dispersion of magnons. Also interaction effects are important to explain the apparent universality of generalized Bloch law exponents e_B, defined by M_s(T)= M_s(0)-const. x T^{e_B}, valid in a wide temperature range T_1 < T < T_2, and for dimensionalities d = 1, 2, and 3. The above-mentioned temperature range, the 'Bloch range', lies above the quantum range, where magnetic long-range order (e.g. in d=2 dimensions) is nontrivially enforced by the additional interactions, but below the thermal critical region, where universal 'anomalous scaling dimensions' apply. In contrast, for the Bloch temperature region, the universality is only apparent, i.e. a crossover-phenomenon, and simple scaling considerations with 'normal dimensions' apply. However, due to interactions, the Bloch exponent e_B depends not only on the dimensionality d of the system, but also on the spin quantum number s (mod (1/2)) of the system, i.e. for given d the Bloch exponent e_B is different for half-integer s and for integer s.Comment: LATEX, 27 pages (including 5 eps-figures); accepted by JMM