Scrollar invariants, syzygies and representations of the symmetric group II

Let $\varphi: C\to \mathbb{P}^1$ be a degree $d$ cover of curves. In work by Castryck, Zhao and the author, we showed how one can attach to each partition $\lambda$ of $d$ a multi-set of scrollar invariants of $\lambda$ with respect to $\varphi$. We studied these invariants when $\varphi$ is simply branched, and related these new scrollar invariants to known geometric data. In this article we show how one can remove this simple branching condition, using the notion of $S_d$-closure as developed by Bhargava and Satriano. With this new framework, we are able to generalize all results from this work to arbitrary covers $C\to \mathbb{P}^1$. In particular, we obtain a syzygy-free interpretation for the splitting types of the syzygy bundles in the Casnati--Ekedahl resolution of an arbitrary cover $\varphi: C\to \mathbb{P}^1$. By using the Maroni bound, we are able to give new general bounds on these splitting types.Comment: 37 pages, comments welcome

The Immigrant Organising Process

This study focuses on the emergence and persistence of immigrant organisations in host societies. The relevance of immigrant organisations for both the host society and the immigrants themselves has been effectively demonstrated in many different studies. However, the question why immigrant organisations emerge and why they often persist over a long period is not adequately answered. In this study a comparative approach is used to reveal the structural determinants of the immigrant organising process. Different theoretical perspectives are combined (immigration model, social movement theory and the organisational ecology model). It is this combination of models, which has not yet been done by other scholars, which determines the value of this study and the contribution to a better understanding of the immigrant organising process. A comparative method is used, analysing Turkish organisations in Amsterdam and Berlin and Surinamese organisations in Amsterdam (1960-2000), to explain the way in which the three explanatory models can be combined in one coherent explanation.This study focuses on the emergence and persistence of immigrant organisations in host societies. The relevance of immigrant organisations for both the host society and the immigrants themselves has been effectively demonstrated in many different studies. However, the question why immigrant organisations emerge and why they often persist over a long period is not adequately answered. In this study a comparative approach is used to reveal the structural determinants of the immigrant organising process. Different theoretical perspectives are combined (immigration model, social movement theory and the organisational ecology model). It is this combination of models, which has not yet been done by other scholars, which determines the value of this study and the contribution to a better understanding of the immigrant organising process. A comparative method is used, analysing Turkish organisations in Amsterdam and Berlin and Surinamese organisations in Amsterdam (1960-2000), to explain the way in which the three explanatory models can be combined in one coherent explanation

Urban inequalities and the identity-to-politics link in the Netherlands and Nigeria

This article examines urban inequalities and minority politics in Amsterdam (the Netherlands) and Jos (Nigeria). Though advanced democracies are considered to be generally more egalitarian than their emergent counterparts, there is very little, if any, scholarly attention dedicated to understanding the specific ways in which the dimensions and parameters of inequalities resemble or contrast between the two contexts. Moreover, while there is growing interest in the identity-to-politics link among urban groups, there is very little comparative sense of how the processes play out across different contexts. Based on a critical analysis of theoretical and empirical perspectives, we show that in Amsterdam, an anti-Muslim discourse, rather than group level inequalities, led to the politicization of immigrant groups. In Jos, however, minority politics is driven by a strong overlap between ascribed identities and inequalities. Though the identity-to-politics link is characterised by a complex set of processes in both cases, the outcomes vary. While minority groups in Amsterdam articulate and pursue their interests within the confines of a well-regulated political space, parties in Jos deploy violent strategies in pursuing their interests because of the prevalence of weak institutions and an unregulated political space that operates on a winner-takes-all logic. The conclusion reiterates a few key insights derived from this cross-fertilization

Frontiers of Ethnic Brutality in an African City: Explaining the Spread and Recurrence of Violent Conflict in Jos, Nigeria

There is considerable consensus among scholars of ethnic riots that ethnically mixed areas are more prone to collective violence than segregated ones. The conclusion is based on studies that compare levels of violence between segregated and mixed localities. While this addresses disparities between settlements of dissimilar ethnic composition, variations in the spread of violence across ethnically mixed areas remain a mystery. Seeking to explicate these variations, we propose an approach that examines not only the ethnic composition of a neighbourhood, but also its location in relation to adjoining neighbourhoods of similar or dissimilar ethnic makeup and their shared boundaries. Based on ethnographic fieldwork in Jos, a violence-ridden Nigerian city, we demonstrate that ethnically mixed areas located between segregated ones experience more incidents of violence than mixed neighbourhoods not comparably located. Our findings have both academic and practical implications.Forschung zu ethnischer Gewalt hat gezeigt, dass ethnisch durchmischte Siedlungsgebiete anfälliger für kollektive Gewalt sind als segregierte. Diese Schlussfolgerung basiert auf Studien, die das Ausmaß der Gewalt zwischen segregierten und durchmischten Orten vergleichen. Im Gegensatz dazu ist völlig unklar, wie sich Varianz bei der Verbreitung von Gewalt in ethnisch durchmischten Gebieten erklären lässt. Um diese Varianz zu erläutern, schlagen wir einen Ansatz vor, der nicht nur die ethnische Zusammensetzung eines Viertels untersucht, sondern auch seinen Nachbarschaft zu Vierteln mit ähnlicher oder unterschiedlicher ethnischer Zusammensetzung und deren gemeinsame Grenzen einbezieht. Basierend auf ethnographischer Feldforschung in Jos, einer nigerianischen Stadt, die wiederkehrende Gewaltkonflikt erlebt hat, zeigen wir, dass ethnisch gemischte Gebiete, die sich zwischen segregierten Orten befinden, mehr Gewaltausbrüche erfahren als durchmischte Viertel ohne eine vergleichbare Nachbarschaft. Daraus lassen sich wichtige wissenschaftliche und praktische Schlussfolgerungen ableiten

A Sikil interlude at Dor: an analysis of contrasting opinions

This paper analyses the opposing views regarding the presence or absence of the Sikil at Dor in Palestine during Early Iron Age 1. Textual sources claim that the Sikil were pirates who came from the west and settled in Cyprus. Egyptian sources point to a Sikil presence at Dor. Some scholars regard the Egyptian sources and archaeological finds at Dor as evidence of a Sikil settlement at Dor. Others maintain that there is a continuity of ceramics at Dor from Canaanite to Phoenician. Though there were foreign influences at Dor during Early Iron Age 1 which point to newcomers, they propose that these newcomers probably came from Cyprus. No archaeological record of a Sea People-presence at Dor has been discovered. This study textually traces the Sikil from the Aegean to Cyprus, Egypt and finally to Dor and a theory is presented that the Sikil originated in the Aegean, temporarily settled in Cyprus and finally at Dor.Biblical and Ancient StudiesM.A. (Biblical Archaeology

Egyptian religious symbols in Judah and Israel from 900 B.C.E. to 587 B.C.E. : a study of seal inconography

When cultures meet, mutual influences and cultural exchanges are unavoidable. Egypt’s contact with Syro-Palestine goes back to at least the Chalcolithic Period. Egypt was a major role player in the region throughout the Bronze Age. The discoveries at Ugarit have placed a lot of emphasis on possible Canaanite influences on the religion of ancient Israel. The purpose of this study is to investigate if cultural exchanges led to Egyptian religious concepts being accepted in Israel and Judah during the period 900-587 B.C.E. (Iron IIB and C). For this reason the iconography on contemporary seals was investigated. Symbols in ancient times, especially amongst illiterate societies, were important instruments in conveying ideas and concepts. The Hebrew Bible abounds with symbolism to illustrate the powers of Yahweh. Egyptian iconography on Hebrew seals, in particular seal amulets, has been regarded by most biblical scholars as mere decorations and the amulets regarded as ‘good luck’ charms. Seal amulets were important instruments of magical ritual in ancient Egypt, where there was no distinction between magic and religion. Biblical prohibitions against magic show that in Israel and Judah, it was regarded as a form of idolatry, thus religious rituals. An important factor to be considered is the influence of Phoenicia on the region during the Period. Close relationships seem to have existed between Phoenicia with the United Kingdom of Israel and later with the northern Kingdom of Israel. An investigation of Phoenician seals from the period revealed that Egyptian religious iconography was used by all levels of Phoenician society. They inter alia used Egyptian imagery to portray their own gods. Seals from Israel and Judah during Iron IIB and C indicate that Egyptian religious iconography was also used on seals by all levels of society in those kingdoms. Israel, due to its close proximity to Phoenicia, probably imported these images via Phoenicia. Judah, due to its isolation, probably got those images directly from Egypt. Some of these images may be ascribed to attempts to portray aspects of Yahweh’s powers. Others convey definite Egyptian religious messages. Egyptian influences on Israelite religion played a larger role than previously accepted.Biblical ArchaeologyD. Litt. et Phil. (Biblical Archaeology

Improvements on dimension growth results and effective Hilbert's irreducibility theorem

We sharpen and generalize the dimension growth bounds for the number of points of bounded height lying on an irreducible algebraic variety of degree $d$, over any global field. In particular, we focus on the the affine hypersurface situation by relaxing the condition on the top degree homogeneous part of the polynomial describing the affine hypersurface. Our work sharpens the dependence on the degree in the bounds, compared to~\cite{CCDN-dgc}. We also formulate a conjecture about plane curves which gives a conjectural approach to the uniform degree $3$ case (the only case which remains open). For induction on dimension, we develop a higher dimensional effective version of Hilbert's irreducibility theorem.Comment: 35 page