Hopf and Lie algebras in semi-additive Varieties

We study Hopf monoids in entropic semi-additive varieties with an emphasis on adjunctions related to the enveloping monoid functor and the primitive element functor. These investigations are based on the concept of the abelian core of a semi-additive variety variety and its monoidal structure in case the variety is entropic.Comment: 13 page

Translocal resilience in a changing environment : Rural-urban migration, livelihood risks, and adaptation in Thailand

This dissertation addresses the intersection of rural livelihoods, resilience towards risks and changes, and migration. By and large, it spotlights the migration–resilience interaction in the con-text of rural transition from an everyday-life perspective by elucidating the role of rural–urban migration for rural livelihoods undergoing change, i.e. against the backdrop of environmental stress and changing weather patterns, amongst other factors. More specifically, it explores how connections between migrants and their respective households of origin influence capacities and resources of these households, located in rural areas, to manage risks and opportunities in a changing environment. The aim is thus to comprehend how migrant–household connections between the places of origin and destination shape the social resilience of households across space and place boundaries. Emphasis is placed on the circumstances of migration and its potentials for the social resilience of migrant households. Moreover, the thesis focuses on domestic migration; specifically, rural–urban migration in Thailand has served as the empirical example. To better comprehend the intersection of rural–urban (migration-related) exchange relations and strategies for facing risks in agriculture-based livelihoods, a practice-oriented translocal-resilience approach has been developed which accommodates place- and scale-specificity and spotlights the interlacing of places through connections and multiple socio-spatial embeddedness. Hence, the circumstances, overlapping positionings, and interconnected everyday activities at both migrants’ places of origin and destination are addressed at the same time. Accordingly, this thesis’ empirical data basis was produced by means of a multi-sited research strategy. This involved the use of mixed-methods in three rural study sites in North and Northeast Thailand and in peri-/urban neighborhoods in Bangkok (Metropolitan Region). The research shows that the circumstances in translocal relations affect households’ livelihoods and resilience differently, ranging from stabilizing to destabilizing effects for both the migrant at the place of destination and the household at the place of origin. The first conclusion is therefore that, to comprehend the links between migration and ways of dealing with environmental change, including impact from climate change, both everyday practices and circumstances in multiple specific places and factors and variables on more encompassing levels than those of the individual and household need to be taken into account, including socially constructed and constantly renegotiated gender and class relations, socio-economic circumstances, and the rural–urban interlacing beyond individual migrant–household connections. Secondly, this study’s results suggest that the area of responsibility for dealing with environmental risks and change, including, for instance adaptation to climate change, cannot be devolved to individual households and migrants, despite their agency and partially extended room for maneuver through migration and translocal connections. On a conceptual level, this thesis shows that social resilience, viewed from a translocal and practice-focused perspective, enables a profound analysis, and therefore a more nuanced understanding of migration impacts in the context of environmental risks and change

The history of the General Adjoint Functor Theorem

Not only motivated by the fact that the publication of the GAFT first appeared 60 years ago in print we reconstruct its history and so show that it is no exaggeration to claim that it has appeared already 75 years ago

On epimorphisms and monomorphisms of Hopf algebras

We provide examples of non-surjective epimorphisms $H\to K$ in the category of Hopf algebras over a field, even with the additional requirement that $K$ have bijective antipode, by showing that the universal map from a Hopf algebra to its enveloping Hopf algebra with bijective antipode is an epimorphism in \halg, although it is known that it need not be surjective. Dual results are obtained for the problem of whether monomorphisms in the category of Hopf algebras are necessarily injective. We also notice that these are automatically examples of non-faithfully flat and respectively non-faithfully coflat maps of Hopf algebras.Comment: 17 pages; changed the abstract, revised introduction, shortened some proofs; to appear in J. Algebr

Simplicial presheaves of coalgebras

The category of simplicial R-coalgebras over a presheaf of commutative unital rings on a small Grothendieck site is endowed with a left proper, simplicial, cofibrantly generated model category structure where the weak equivalences are the local weak equivalences of the underlying simplicial presheaves. This model category is naturally linked to the R-local homotopy theory of simplicial presheaves and the homotopy theory of simplicial R-modules by Quillen adjunctions. We study the comparison with the R-local homotopy category of simplicial presheaves in the special case where R is a presheaf of algebraically closed (or perfect) fields. If R is a presheaf of algebraically closed fields, we show that the R-local homotopy category of simplicial presheaves embeds fully faithfully in the homotopy category of simplicial R-coalgebras.Comment: 24 page

Selected results from the NORC general social survey and the German general social survey (ALLBUS) of 1982: a cross national comparison

Die Verfasser stellen Teilergebnisse eines Vergleiches zwischen den amerikanischen NORC General Social Surveys und dem deutschen ALLBUS 1982 (Allgemeine Bevölkerungsumfrage der Sozialwissenschaften, ZUMA) vor. Dem ALLBUS 1982 werden dabei die General Social Surveys von 1976, 1977, 1980 und 1982 gegenübergestellt. Die Studien werden einleitend kurz beschrieben (Populationen, Stichproben, Stichprobenverfahren, Untersuchungszeiträume). Der Vergleich selbst bezieht sich auf soziodemographische Aspekte (Alter der Befragten, Geschlecht, Ausbildungsstand, Beschäftigung) und auf Einstellungen und Werthaltungen (Bedeutung der verschiedenen Lebenssphären für die Befragten in der Bundesrepublik und den USA, ideale Kinderzahl, Erziehungsziele, Rolle der Frau, Abtreibung, Anomie, Berufsorientierungen, subjektive Schichteneinschätzung, Einstellung zu den Nachbarn, Rüstungs- und generell Staatsausgaben). Im Anschluß an die tabellarische Gegenüberstellung der jeweiligen Zahlen findet sich ein Kommentar zu den Ähnlichkeiten und Unterschieden zwischen den amerikanischen und deutschen Ergebnissen. (JL