Braided Oscillators

The braided Hopf algebra structure of the generalized oscillator is investigated. Using the solutions two types of braided Fibonacci oscillators are introduced. This leads to two types of braided Biedenharn-Macfarlane oscillators.Comment: 12 pages, latex, some references added, published versio

The impact of bullying on students’ learning in Latin America: A matching approach for 15 countries

We examine the impact of bullying on learning and non-cognitive outcomes for sixth grade students in 15 Latin America countries using data from the Third Regional Comparative and Explanatory Study (TERCE) learning survey. We apply OLS and propensity score matching to attenuate the impact of confounding factors. Matching results show that students being bullied achieve between 9.6 and 18.4 points less in math than their non-bullied peers whilst in reading between 5.8 and 19.4 lower scores, a 0.07-0.22 reduction in the standard deviation of test scores. Thus, substantial learning gains could be accomplished by anti-bullying policies in the region

Intergenerational Education Effects of Early Marriage in Sub-Saharan Africa

This paper analyzes the evolution of the effects on educational inequality of early marriage by looking at the impact of whether women had married young on their children’s schooling outcomes for 25–32 countries (Demographic and Health Surveys) in 2000 and 2010 for Sub-Saharan Africa. We also explore indirect pathways—mother’s education, health, and empowerment as well as community channels—operating from early marriage to child schooling and assess the presence of negative externalities for non-early married mothers and their children on education transmission in communities with large rates of child marriage. In our econometric analysis we employ OLS, matching, instrumental variables, and pseudo-panel for a better understanding of changes over time. Our results show that early marriage is still a significant source of inequality, though its impact has decreased across time: girls born to early married mothers are between 6% and 11% more likely to never been to school and 1.6% and 1.7% to enter late, and 3.3% and 5.1% less likely to complete primary school, whereas boys are between 5.2% and 8.8% more likely to never been to school and 1% and 1.9% to enter late, and 2.3% and 5.5% less likely to complete primary school. Second, child marriage increases gender inequality within household’s with girls losing an additional 0.07 years of schooling as compared to boys if born to early married mothers. Third, our estimates show that mother’s education and health mediate some of the effect of early marriage and that the large prevalence of child marriage in a community also impairs educational transmission for non-early married mothers. Fourth, empowering of young wives can weaken other channels of transmission of education inequalities. Overall, our findings highlight the need to target these children with the appropriate interventions and support to achieve the greater focus on equity in the global post-2015 education agenda

Symmetry Breaking in the Schr\"odinger Representation for Chern-Simons Theories

This paper discusses the phenomenon of spontaneous symmetry breaking in the Schr\"odinger representation formulation of quantum field theory. The analysis is presented for three-dimensional space-time abelian gauge theories with either Maxwell, Maxwell-Chern-Simons, or pure Chern-Simons terms as the gauge field contribution to the action, each of which leads to a different form of mass generation for the gauge fields.Comment: 16pp, LaTeX , UCONN-94-

Functional Determinants in Quantum Field Theory

Functional determinants of differential operators play a prominent role in theoretical and mathematical physics, and in particular in quantum field theory. They are, however, difficult to compute in non-trivial cases. For one dimensional problems, a classical result of Gel'fand and Yaglom dramatically simplifies the problem so that the functional determinant can be computed without computing the spectrum of eigenvalues. Here I report recent progress in extending this approach to higher dimensions (i.e., functional determinants of partial differential operators), with applications in quantum field theory.Comment: Plenary talk at QTS5 (Quantum Theory and Symmetries); 16 pp, 2 fig

Problems With Complex Actions

We consider Euclidean functional integrals involving actions which are not exclusively real. This situation arises, for example, when there are $t$-odd terms in the the Minkowski action. Writing the action in terms of only real fields (which is always possible), such terms appear as explicitly imaginary terms in the Euclidean action. The usual quanization procedure which involves finding the critical points of the action and then quantizing the spectrum of fluctuations about these critical points fails. In the case of complex actions, there do not exist, in general, any critical points of the action on the space of real fields, the critical points are in general complex. The proper definition of the function integral then requires the analytic continuation of the functional integration into the space of complex fields so as to pass through the complex critical points according to the method of steepest descent. We show a simple example where this procedure can be carried out explicitly. The procedure of finding the critical points of the real part of the action and quantizing the corresponding fluctuations, treating the (exponential of the) complex part of the action as a bounded integrable function is shown to fail in our explicit example, at least perturbatively.Comment: 6+epsilon pages, no figures, presented at Theory CANADA

Simplified Vacuum Energy Expressions for Radial Backgrounds and Domain Walls

We extend our previous results of simplified expressions for functional determinants for radial Schr\"odinger operators to the computation of vacuum energy, or mass corrections, for static but spatially radial backgrounds, and for domain wall configurations. Our method is based on the zeta function approach to the Gel'fand-Yaglom theorem, suitably extended to higher dimensional systems on separable manifolds. We find new expressions that are easy to implement numerically, for both zero and nonzero temperature.Comment: 30 page

Exploring scholarly data with Rexplore.

Despite the large number and variety of tools and services available today for exploring scholarly data, current support is still very limited in the context of sensemaking tasks, which go beyond standard search and ranking of authors and publications, and focus instead on i) understanding the dynamics of research areas, ii) relating authors ‘semantically’ (e.g., in terms of common interests or shared academic trajectories), or iii) performing fine-grained academic expert search along multiple dimensions. To address this gap we have developed a novel tool, Rexplore, which integrates statistical analysis, semantic technologies, and visual analytics to provide effective support for exploring and making sense of scholarly data. Here, we describe the main innovative elements of the tool and we present the results from a task-centric empirical evaluation, which shows that Rexplore is highly effective at providing support for the aforementioned sensemaking tasks. In addition, these results are robust both with respect to the background of the users (i.e., expert analysts vs. ‘ordinary’ users) and also with respect to whether the tasks are selected by the evaluators or proposed by the users themselves

Chern-Simons Solitons, Chiral Model, and (affine) Toda Model on Noncommutative Space

We consider the Dunne-Jackiw-Pi-Trugenberger model of a U(N) Chern-Simons gauge theory coupled to a nonrelativistic complex adjoint matter on noncommutative space. Soliton configurations of this model are related the solutions of the chiral model on noncommutative plane. A generalized Uhlenbeck's uniton method for the chiral model on noncommutative space provides explicit Chern-Simons solitons. Fundamental solitons in the U(1) gauge theory are shaped as rings of charge `n' and spin `n' where the Chern-Simons level `n' should be an integer upon quantization. Toda and Liouville models are generalized to noncommutative plane and the solutions are provided by the uniton method. We also define affine Toda and sine-Gordon models on noncommutative plane. Finally the first order moduli space dynamics of Chern-Simons solitons is shown to be trivial.Comment: latex, JHEP style, 23 pages, no figur