Heavy Meson Masses in the \epsilon-Regime of HM\chi PT

The pseudoscalar and vector heavy meson masses are calculated in the \epsilon-regime of Heavy Meson Chiral Perturbation Theory to order \epsilon^4. The results of this calculation will allow the determination of low-energy coefficients (LECs) directly from Lattice QCD calculations of the heavy mesons masses for lattices that satisfy the \epsilon-regime criteria. In particular, the LECs that parametrize the NLO volume dependance of the heavy meson masses are necessary for evaluating the light pseudoscalar meson (\pi, K, \eta) and heavy meson ({D^0, D^+, D^+_s}, {B^-,\bar{B}^0,\bar{B}^0_s}) scattering phase shifts.Comment: 16 pages, 6 figure

Mathematics from China to Virginia by Way of Singapore

Our article follows from an interesting concurrence of mathematical and educational lines. At least the concurrence seems so to us and we hope that those who read on will agree. The lines or streams are a joint minimester program at St. Catherine’s and St. Christopher‘s Schools, an interest in problem solving, and a Singapore connection. We shall describe the lines first and then describe the mathematics that we found at their intersection

Shortcuts to Thermodynamic Computing: The Cost of Fast and Faithful Erasure

Landauer's Principle states that the energy cost of information processing must exceed the product of the temperature and the change in Shannon entropy of the information-bearing degrees of freedom. However, this lower bound is achievable only for quasistatic, near-equilibrium computations -- that is, only over infinite time. In practice, information processing takes place in finite time, resulting in dissipation and potentially unreliable logical outcomes. For overdamped Langevin dynamics, we show that counterdiabatic potentials can be crafted to guide systems rapidly and accurately along desired computational paths, providing shortcuts that allows for the precise design of finite-time computations. Such shortcuts require additional work, beyond Landauer's bound, that is irretrievably dissipated into the environment. We show that this dissipated work is proportional to the computation rate as well as the square of the information-storing system's length scale. As a paradigmatic example, we design shortcuts to erase a bit of information metastably stored in a double-well potential. Though dissipated work generally increases with erasure fidelity, we show that it is possible perform perfect erasure in finite time with finite work. We also show that the robustness of information storage affects the energetic cost of erasure---specifically, the dissipated work scales as the information lifetime of the bistable system. Our analysis exposes a rich and nuanced relationship between work, speed, size of the information-bearing degrees of freedom, storage robustness, and the difference between initial and final informational statistics.Comment: 19 pages, 7 figures; http://csc.ucdavis.edu/~cmg/compmech/pubs/scte.ht

Summer Camp as a Force for 21st Century Learning: Exploring Divergent Thinking and Activity Selection in a Residential Camp Setting

This study investigated change in divergent thinking (DT), an indicator of creative potential, at two gender-specific residential summer camps. Additionally, this study examined whether the change in DT varied by gender and by the type of activities campers self-select. Quantitative methods, using a quasi-experimental design was used in order to understand differences in camper scores. A total of 189 youth, 100 girls, 89 boys, between the ages of 9 and 14 years participated in the current study. Participants were administered a modified version of Guilford\u27s (1967) alternate uses task, a measure of DT, in which respondents were asked questions such as name all of the uses for a brick or name all of the uses for a plate before the camp session started, and then again at the end of the two-week session. Results indicate overall mean significant increases in DT across all scoring methods of fluency, flexibility, and originality. Participants who self-selected one or more artistic activities (e.g., drama, arts and crafts, dance) had significant increases on the tasks as opposed to participants who did not select any artistic activities (e.g., basketball, baseball, archery). Finally, girls significantly increased across all scoring methods, whereas boys slightly increased in fluency and flexibility but not in originality. These results indicate residential summer camp may provide a creativity benefit for youth in attendance, especially those who participate in certain activities. Practitioners should use this study to understand their own programming in terms of creativity, activity offerings, and camp cultur

Bounds on Heavy-to-Heavy Mesonic Form Factors

We provide upper and lower bounds on the form factors for B -> D, D^* by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to leading order in Lambda_QCD/m_Q and alpha_s. The O(alpha_s^2 beta_0) corrections to the bounds at zero recoil are also presented. We compare our bounds with some of the form factor models used in the literature. All the models we investigated failed to fall within the bounds for the combination of form factors (omega^2 - 1)/(4 omega)|omega h_{A2}+h_{A3}|^2.Comment: 27 pages, 10 figure

Two-peaked and flat-top perfect bright solitons in epsilon-near-zero nonlinear metamaterials: novel Kerr self-trapping mechanisms

We analytically investigate transverse magnetic (TM) spatial bright solitons, as exact solutions of Maxwell's equations, propagating through nonlinear metamaterials whose linear dielectric permittivity is very close to zero and whose effective nonlinear Kerr parameters can be tailored to achieve values not available in standard materials. Exploiting the fact that, in the considered medium, linear and nonlinear polarization can be comparable at feasible and realistic optical intensities, we identify two novel self-trapping mechanisms able to support two-peaked and flat-top solitons, respectively. Specifically, these two novel mechanisms are based on the occurrence of critical points at which the effective nonlinear permittivity vanishes, the two mechanisms differing in the way the compensation between linear and nonlinear polarization is achieved through the non-standard values of the nonlinear parameters.Comment: 7 pages, 4 figure

PAH in the laboratory and interstellar space

The theory that polycyclic aromatic hydrocarbons (PAHs) are a constituent of the interstellar medium, and a source of the IR emission bands at 3.3, 6.2, 7.7, 8.6, and 11.3 microns is being studied using PAH containing acid insoluble residue of the Orgueil CI meteorite and coal tar. FTIR spectra of Orgueil PAH material that has undergone thermal treatment, and a solvent insoluble fraction of coal tar that has been exposed to hydrogen plasma are presented. The UV excided luminescence spectrum of a solvent soluble coal tar film is also shown. Comparison of the lab measurements with observations appears to support the interstellar PAH theory, and shows the process of dehydrogenation expected to take place in the interstellar medium

Polarization squeezing of light by single passage through an atomic vapor

We have studied relative-intensity fluctuations for a variable set of orthogonal elliptic polarization components of a linearly polarized laser beam traversing a resonant $^{87}$Rb vapor cell. Significant polarization squeezing at the threshold level (-3dB) required for the implementation of several continuous variables quantum protocols was observed. The extreme simplicity of the setup, based on standard polarization components, makes it particularly convenient for quantum information applications.Comment: Revised version. Minor changes. four pages, three figure