Attosecond streaking enables the measurement of quantum phase

Attosecond streaking, as a measurement technique, was originally conceived as a means to characterize attosecond light pulses, which is a good approximation if the relevant transition matrix elements are approximately constant within the bandwidth of the light pulse. Our analysis of attosecond streaking measurements on systems with complex response to the photoionizing pulse establishes a relation between the momentum-space wave function of the outgoing electron and the result of conventional retrieval algorithms. This finding enables the measurement of the quantum phase associated with bound-continuum transition matrix elements.Comment: similar to the version accepted for publication in PR

Coping and Gender Differences in Seasonality and Seasonal Affective Disorder

Research indicates an individual’s tendency to ruminate in response to seasonal changes predicts the severity of seasonality as well as Seasonal Affective Disorder (SAD). However, research on the relationship between other coping strategies and SAD is sparse. My hypothesis was that maladaptive coping strategies such as mental disengagement would be related to higher levels of SAD. My research used archival data from 607 undergraduate students who reported on SAD symptoms and a variety of other measures. Statistically significant differences between coping strategies were found for women and men. In addition, predictors of seasonality were not consistent across gender. The present study identifies gender-specific factors related to seasonality

Group classification of (1+1)-Dimensional Schr\"odinger Equations with Potentials and Power Nonlinearities

We perform the complete group classification in the class of nonlinear Schr\"odinger equations of the form $i\psi_t+\psi_{xx}+|\psi|^\gamma\psi+V(t,x)\psi=0$ where $V$ is an arbitrary complex-valued potential depending on $t$ and $x,$ $\gamma$ is a real non-zero constant. We construct all the possible inequivalent potentials for which these equations have non-trivial Lie symmetries using a combination of algebraic and compatibility methods. The proposed approach can be applied to solving group classification problems for a number of important classes of differential equations arising in mathematical physics.Comment: 10 page

Social Structure, Markets and Inequality

The interaction between social structure and markets remains a central theme in the social sciences. In some instances, markets can build on and enhance social networks' economic role; in other contexts, markets appear to be in direct competition with social networks. The impact of markets on inequality and welfare is also varying: while markets can sometimes offer valuable outside options to marginalised individuals, in other situations only well connected and better off individuals can benefit from them. In this paper, our goal is to understand the economic mechanisms that can explain these different empirical patterns. We develop a simple model that combines social networks and a mix of network-exchange and market-exchange activities. The key to understanding the empirical patterns and phenomena lies in the relation between the two activities i.e., whether they are (strategic) complements or substitutes. Social connectedness facilitates the adoption of the market action if the two activities are complements; the converse is true in case of substitutes. Inequality in a social structure is typically reinforced by the market in case the two actions are complements; the converse holds true if they are substitutes