New results on the spectroscopy of XYZ states from LHC experiments

The main results from LHC experiments on XYZ charmonium-like candidates are summarized.Comment: to appear in the proceedings of The 5th International Workshop on Charm Physics (Charm 2012

Strategies for Optimize Off-Lattice Aggregate Simulations

We review some computer algorithms for the simulation of off-lattice clusters grown from a seed, with emphasis on the diffusion-limited aggregation, ballistic aggregation and Eden models. Only those methods which can be immediately extended to distinct off-lattice aggregation processes are discussed. The computer efficiencies of the distinct algorithms are compared.Comment: 6 pages, 7 figures and 3 tables; published at Brazilian Journal of Physics 38, march, 2008 (http://www.sbfisica.org.br/bjp/files/v38_81.pdf

INTERRELATED BANK STRATEGIES, FINANCIAL FRAGILITY AND CREDIT EXPANSION: A POST KEYNESIAN APPROACH

This paper aims at clarifying the relationship between individual bank and banking industry behavior in credit expansion. We argue that the balance sheet structure of an individual bank is only partially determined by its management decision about how aggressively to expand credit; it is also determined by the balance sheet positions of other banks. This relationship is explicitly shown by a disaggregation of the variable that enters into the simple money multiplier. The approach developed here opens a way to integrating the micro and macro levels in a Keynesian banking-system analysis.

Cities: continuity, transformation, and emergence

Cities can be regarded as the quintessential example of complexity. Insofar as we can define a hidden hand determining their morphology, this is based on the glue that stitches together the actions of individuals and organizations who build the city from the ground-up, so-to-speak. When general systems theory entered the lexicon of science in the mid- 20th century, cities were regarded as being excellent examples of systems with interactions between basic elements that demonstrated the slogan of the field: the ‘whole is greater than the sum of the parts’. Since then, as complexity theory has evolved to embrace systems theory and as temporal dynamics has come onto the agenda, cities once again have been used to illustrate basic themes: global organization from local action, emergent morphology from simple spatial decision, temporal order at global levels from volatile, seemingly random change at the level of individual decision-making, evolution and progress through coevolution, competition, and endless variety. Here we will sketch these ideas with respect to cities illustrating particularly three key ideas which involve the tension between continuously changing systems, qualitative transformations, and radical change based on emergent properties of the whole. Our analysis has many implications for a new theory of urban planning which is built from the bottom up, rather than from the top down which is the traditional way in which such interventions are currently carried out in the name of making better cities. Contemporary problems such as ethnic segregation, urban sprawl, traffic congestion, urban decline, and regeneration are all informed by the perspective on complexity theory that we bring to bear here

Amplitude analysis of four-body decays using a massively-parallel fitting framework

The GooFit Framework is designed to perform maximum-likelihood fits for arbitrary functions on various parallel back ends, for example a GPU. We present an extension to GooFit which adds the functionality to perform time-dependent amplitude analyses of pseudoscalar mesons decaying into four pseudoscalar final states. Benchmarks of this functionality show a significant performance increase when utilizing a GPU compared to a CPU. Furthermore, this extension is employed to study the sensitivity on the $D^0 - \bar{D}^0$ mixing parameters $x$ and $y$ in a time-dependent amplitude analysis of the decay $D^0 \rightarrow K^+\pi^-\pi^+\pi^-$. Studying a sample of 50 000 events and setting the central values to the world average of $x = (0.49 \pm0.15) \%$ and $y = (0.61 \pm0.08) \%$, the statistical sensitivities of $x$ and $y$ are determined to be $\sigma(x) = 0.019 \%$ and $\sigma(y) = 0.019 \%$.Comment: Proceedings of the 22nd International Conference on Computing in High Energy and Nuclear Physics, CHEP 201