Classical and quantum anomalous diffusion in a system of 2δ\delta-kicked Quantum Rotors

We study the dynamics of cold atoms subjected to {\em pairs} of closely time-spaced $\delta$-kicks from standing waves of light. The classical phase space of this system is partitioned into momentum cells separated by trapping regions. In a certain range of parameters it is shown that the classical motion is well described by a process of anomalous diffusion. We investigate in detail the impact of the underlying classical anomalous diffusion on the quantum dynamics with special emphasis on the phenomenon of dynamical localization. Based on the study of the quantum density of probability, its second moment and the return probability we identify a region of weak dynamical localization where the quantum diffusion is still anomalous but the diffusion rate is slower than in the classical case. Moreover we examine how other relevant time scales such as the quantum-classical breaking time or the one related to the beginning of full dynamical localization are modified by the classical anomalous diffusion. Finally we discuss the relevance of our results for the understanding of the role of classical cantori in quantum mechanics.Comment: 9 pages, 3 figure

Impact of two mass-scale oscillations on the analysis of atmospheric and reactor neutrino data

We study the stability of the results of 3-nu oscillation analysis of atmospheric and reactor neutrino data under departures of the one--dominant mass scale approximation. In order to do so we perform the analysis of atmospheric and reactor neutrino data in terms of three--neutrino oscillations where the effect of both mass differences is explicitly considered. We study the allowed parameter space resulting from this analysis as a function of the mass splitting hierarchy parameter alpha = Delta m^2/Delta M^2 which parametrizes the departure from the one--dominant mass scale approximation. We consider schemes with both direct and inverted mass ordering. Our results show that in the analysis of atmospheric data the derived range of the largest mass splitting, Delta M^2$, is stable while the allowed ranges of mixing angles sin^2 theta_{23} and sin^2 theta_{13} are wider than those obtained in the one--dominant mass scale approximation. Inclusion of the CHOOZ reactor data in the analysis results into the reduction of the parameter space in particular for the mixing angles. As a consequence the final allowed ranges of parameters from the combined analysis are only slightly broader than when obtained in the one--dominant mass scale approximation.Comment: Updated data, references added and typos corrected. Version to appear in Eur.Phys.J.

Honoring, Training, and Building a Statewide Network of Elder Activists: The California Senior Leaders Program (2002-2012)

This case study explores the first decade (2002-2012) of the California Senior Leaders Program (CSLP), including participants' creation of a formal advocacy group, the California Senior Leaders Alliance. Grounded in concerns with ageism and invisibility, the CSLP provides recognition and support for diverse California elders engaged in community building and social justice work. This study employs qualitative analysis of data from participant interviews, event evaluations, program documents, video footage, and participant observation. Findings show emotional, learning, and networking benefits for participants, intergenerational influences, collective capacity and coalition building, and contributions to policy. Program challenges are described, and future directions discussed. © 2013 Copyright Taylor and Francis Group, LLC

The QCD vacuum as a disordered medium: A simplified model for the QCD Dirac operator

We model the QCD Dirac operator as a power-law random banded matrix (RBM) with the appropriate chiral symmetry. Our motivation is the form of the Dirac operator in a basis of instantonic zero modes with a corresponding gauge background of instantons. We compare the spectral correlations of this model to those of an instanton liquid model (ILM) and find agreement well beyond the Thouless energy. In the bulk of the spectrum the (dimensionless) Thouless energy of the RBM scales with the square root of system size in agreement with the ILM and chiral perturbation theory. Near the origin the scaling of the (dimensionless) Thouless energy in the RBM remains the same as in the bulk which agrees with chiral perturbation theory but not with the ILM. Finally we discuss how this RBM should be modified in order to describe the spectral correlations of the QCD Dirac operator at the finite temperature chiral restoration transition.Comment: 4 pages, 3 figure