"Reconsidering Citizenship and Nationhood in France and Germany: The Integration of the 21st-century Gastarbeiter"

In the generous welfare states of Europe, one of the most obvious benefits of citizenship is participation in national health insurance plans. With academics and politicians discussing the possibility of a “European welfare state,” it has become crucial to examine the types of definitions the Union might use to create this supranational institution. Rogers Brubaker has opposed the French and German conceptions of citizenship, with German citizenship being transmitted almost exclusively by blood relation (jus sanguinis) and French citizenship being extended to those having proven residence in France (jus solis). Although the immigration reforms of 2003 have permitted second-generation Turkish immigrants in Germany to more easily achieve citizenship status, it remains that many German Turks are excluded from many of the benefits of citizenship. By contrast, France strives to remain the model of jus solis par excellence. Recently, these two countries have progressively begun to extend welfare state benefits to immigrants; movements on behalf of this type of measure have increased in prominence in France since the riots of 2005. This paper develops a mechanism to explain how national models of citizenship have recently granted or limited access to the welfare state; and, conversely, how access to the welfare state can serve to define the citizen. Using the data of the major public opinion surveys and interviews with immigrant communities as well as French and German nationals, it will attempt to construct a model of the public conception of citizenship as based on access to the welfare state. Most importantly, however, the results of these findings will be used to comment on the possibilities for the use of the welfare state as a tool of integration, both nationally and at the EU level

Discrete Light-Cone Quantization in PP-Wave Background

We discuss the discrete light-cone quantization (DLCQ) of a scalar field theory on the maximally supersymmetric pp-wave background in ten dimensions. It has been shown that the DLCQ can be carried out in the same way as in the two-dimensional Minkowski spacetime. Then, the vacuum energy is computed by evaluating the vacuum expectation value of the light-cone Hamiltonian. The results are consistent with the effective potential obtained in our previous work [hep-th/0402028].Comment: 11pages, LaTeX, to appear in Phys. Lett.

Fermi Coordinates and Penrose Limits

We propose a formulation of the Penrose plane wave limit in terms of null Fermi coordinates. This provides a physically intuitive (Fermi coordinates are direct measures of geodesic distance in space-time) and manifestly covariant description of the expansion around the plane wave metric in terms of components of the curvature tensor of the original metric, and generalises the covariant description of the lowest order Penrose limit metric itself, obtained in hep-th/0312029. We describe in some detail the construction of null Fermi coordinates and the corresponding expansion of the metric, and then study various aspects of the higher order corrections to the Penrose limit. In particular, we observe that in general the first-order corrected metric is such that it admits a light-cone gauge description in string theory. We also establish a formal analogue of the Weyl tensor peeling theorem for the Penrose limit expansion in any dimension, and we give a simple derivation of the leading (quadratic) corrections to the Penrose limit of AdS_5 x S^5.Comment: 25 page

Blackfolds, Plane Waves and Minimal Surfaces

Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.Comment: v2: 67pp, 7figures, typos fixed, matches published versio

Penrose limits of homogeneous spaces

We prove that the Penrose limit of a spacetime along a homogeneous geodesic is a homogeneous plane wave spacetime and that the Penrose limit of a reductive homogeneous spacetime along a homogeneous geodesic is a Cahen--Wallach space. We then consider several homogenous examples to show that these results are indeed sharp and conclude with a remark about the existence of null homogeneous geodesics.Comment: 16 pages, many changes particularly to sections 6 and

ILR Impact Brief – Gender, Promotion, and Raises: Sometimes the Advantage Goes to Men

Prior studies looking at gender discrimination in the workplace, in the form of promotions and/or raises, have yielded mixed results. Research focusing on promotions has found that women are promoted less often than men, more often than men, and at equal rates. Research assessing both promotions and wages, grounded in the notion that promotions signal a status change that warrants additional compensation, has also produced no consensus on outcomes. This particular study, however, used unique data on recently hired workers at a broad sample of companies that enabled the authors to control for workers’ job performance, educational attainment, and other characteristics, as well as company characteristics such as profit/not-for-profit status, industry, establishment size, and percent of the workforce covered by a union contract in order to analyze gender differences in actual and expected promotions and accompanying wage gains

Asymptotically Schr\"odinger Space-Times

We first review how asymptotically Schr\"odinger space-times arise in a natural way by performing a TsT transformation on asymptotically AdS space-times and some of its consequences. We then give a coordinate independent definition of a pure Schr\"odinger space-time in terms of an AdS metric and an AdS null Killing vector. Then, by analogy with the AdS case, we provide a local and coordinate independent definition of a Schr\"odinger boundary in terms of a defining function. We use this to construct the Fefferman-Graham expansions of locally Schr\"odinger space-times.Comment: 6 pages, based on a contribution to the Proceedings of the XVII European Workshop on String Theory (Padova, 5-9 September 2011