A nonlinear drift which leads to κ\kappa-generalized distributions

We consider a system described by a Fokker-Planck equation with a new type of momentum-dependent drift coefficient which asymptotically decreases as $-1/p$ for a large momentum $p$. It is shown that the steady-state of this system is a $\kappa$-generalized Gaussian distribution, which is a non-Gaussian distribution with a power-law tail.Comment: Submitted to EPJB. 8 pages, 2 figures, dedicated to the proceedings of APFA

Twist-induced snapping in a bent elastic ribbon

Snapping of a slender structure is utilized in a wide range of natural and man-made systems, mostly to achieve rapid movement without relying on muscle-like elements. Although several mechanisms for elastic energy storage and rapid release have been studied in detail, a general understanding of the approach to design such a kinetic system is a key challenge in mechanics. Here we study a twist-driven buckling and fast flip dynamics of a geometrically constraint ribbon by combining experiments, numerical simulations, and analytical theory. We identify two distinct types of shape transitions; a narrow ribbon snaps, whereas a wide ribbon forms a pair of localized helices. We construct a phase diagram and explain the origin of the boundary, which is determined only by geometry. We quantify effects of gravity and clarify time scale dictating the rapid flipping. Our study reveals the unique role of geometric twist-bend coupling on the fast dynamics of a thin constrained structure, which has implications for a wide range of biophysical and applied physical problems.Comment: 5pages, 4 figures, under revie

Well-localized edge states in two-dimensional topological insulators: ultrathin Bi films

We theoretically study the generic behavior of the penetration depth of the edge states in two-dimensional quantum spin Hall systems. We found that the momentum-space width of the edge-state dispersion scales with the inverse of the penetration depth. As an example of well-localized edge states, we take the Bi(111) ultrathin film. Its edge states are found to extend almost over the whole Brillouin zone. Correspondingly, the bismuth (111) 1-bilayer system is proposed to have well-localized edge states in contrast to the HgTe quantum well.Comment: 4 pages, 4 figure

Composition law of κ\kappa-entropy for statistically independent systems

The intriguing and still open question concerning the composition law of $\kappa$-entropy $S_{\kappa}(f)=\frac{1}{2\kappa}\sum_i (f_i^{1-\kappa}-f_i^{1+\kappa})$ with $0<\kappa<1$ and $\sum_i f_i =1$ is here reconsidered and solved. It is shown that, for a statistical system described by the probability distribution $f=\{ f_{ij}\}$, made up of two statistically independent subsystems, described through the probability distributions $p=\{ p_i\}$ and $q=\{ q_j\}$, respectively, with $f_{ij}=p_iq_j$, the joint entropy $S_{\kappa}(p\,q)$ can be obtained starting from the $S_{\kappa}(p)$ and $S_{\kappa}(q)$ entropies, and additionally from the entropic functionals $S_{\kappa}(p/e_{\kappa})$ and $S_{\kappa}(q/e_{\kappa})$, $e_{\kappa}$ being the $\kappa$-Napier number. The composition law of the $\kappa$-entropy is given in closed form, and emerges as a one-parameter generalization of the ordinary additivity law of Boltzmann-Shannon entropy recovered in the $\kappa \rightarrow 0$ limit.Comment: 14 page

Attitudes toward Marriage, Divorce, Cohabitation, and Casual Sex among Working-Age Latinos: Does Religion Matter?

The rapid growth of the Latino population in the United States has renewed interest in Latino family research. It has often been assumed that Catholicism is a key factor influencing Latinos’ attitudes toward the family, despite the fact that nearly one third of Latinos are not Catholic. This article uses data from the 2006 National Survey of Religion and Family Life, a survey of working-age adults (aged 18-59 years) in the lower 48 states, to explore the relationship between multiple dimensions of religiosity—denomination, church attendance, prayer, and beliefs about the Bible—and Latinos’ attitudes regarding marriage, divorce, cohabitation, and casual sex. Compared with Catholics, evangelical Protestants tend to hold more conservative attitudes on family-related issues. Latinos who attend services regularly and pray frequently also report more traditional views. Findings involving literalist views of the Bible are more equivocal. Taken together, religious variables are just as potent as socioeconomic and demographic factors in explaining individual-level variation in Latinos’ attitudes. Study limitations are noted, and several directions for future research are identified

Dynamical Susceptibility in KH2PO4-type Crystals above and below Tc

The time dependent cluster approximation called the path probability method (PPM) is applied to a pseudo-spin Ising Hamiltonian of the Slater-Takagi model for KH2PO4-type hydrogen-bonded ferroelectrics in order to calculate the homogeneous dynamical susceptibility above and below the ferroelectric transition temperature. Above the transition temperature all the calculations are carried out analytically in the cactus approximation of the PPM. Below the transition temperature the dynamical susceptibility is also calculated accurately since the analytical solution of spontaneous polarization in the ferroelectric phase can be utilized. When the temperature is approached from both sides of the transition temperature, only one of relaxation times shows a critical slowing down and makes a main contribution to the dynamical susceptibility. The discrepancy from Slater model (ice-rule limit) is discussed in comparison with some experimental data.Comment: 8 pages, 10 figure

Religion and Attitudes toward Same-Sex Marriage among U.S. Latinos

Objectives. This study examines links between multiple aspects of religious involvement and attitudes toward same-sex marriage among U.S. Latinos. The primary focus is on variations by affiliation and participation, but the possible mediating roles of biblical beliefs, clergy cues, and the role of religion in shaping political views are also considered. Methods. We use binary logistic regression models to analyze data from a large nationwide sample of U.S. Latinos conducted by the Pew Hispanic Forum in late 2006. Results. Findings highlight the strong opposition to same-sex marriage among Latino evangelical (or conservative) Protestants and members of sectarian groups (e.g., LDS), even compared with devout Catholics. Although each of the hypothesized mediators is significantly linked with attitudes toward same-sex marriage, for the most part controlling for them does not alter the massive affiliation/attendance differences in attitudes toward same-sex marriage. Conclusions. This study illustrates the importance of religious cleavages in public opinion on social issues within the diverse U.S. Latino population. The significance of religious variations in Hispanic civic life is likely to increase with the growth of the Latino population and the rising numbers of Protestants and sectarians among Latinos

Neo-Hookean fiber composites undergoing finite out-of-plane shear deformations

The response of a neo-Hookean fiber composite undergoing finite out-of-plane shear deformation is examined. To this end an explicit close form solution for the out-of-plane shear response of a cylindrical composite element is introduced. We find that the overall response of the cylindrical composite element can be characterized by a fictitious homogeneous neo-Hookean material. Accordingly, this macroscopic response is identical to the response of a composite cylinder assemblage. The expression for the effective shear modulus of the composite cylinder assemblage is identical to the corresponding expression in the limit of small deformation elasticity, and hence also to the expression for the Hashin-Shtrikman bounds on the out-of-plane shear modulus