Break-up of Rydberg superatoms via dipole-dipole interactions

We investigate resonant dipole-dipole interactions between two "superatoms" of different angular momentum, consisting of two Rydberg-blockaded atom clouds where each of them carries initially a coherently shared single excitation. We demonstrate that the dipole-dipole interaction breaks up the superatoms by removing the excitations from the clouds. The dynamics is akin to an ensemble average over systems where only one atom per cloud participates in entangled motion and excitation transfer. Our findings should thus facilitate the experimental realization of adiabatic exciton transport in Rydberg systems by replacing single sites with atom clouds.Comment: 10 pages, 5 figure

Distributed Event-Based State Estimation for Networked Systems: An LMI-Approach

In this work, a dynamic system is controlled by multiple sensor-actuator agents, each of them commanding and observing parts of the system's input and output. The different agents sporadically exchange data with each other via a common bus network according to local event-triggering protocols. From these data, each agent estimates the complete dynamic state of the system and uses its estimate for feedback control. We propose a synthesis procedure for designing the agents' state estimators and the event triggering thresholds. The resulting distributed and event-based control system is guaranteed to be stable and to satisfy a predefined estimation performance criterion. The approach is applied to the control of a vehicle platoon, where the method's trade-off between performance and communication, and the scalability in the number of agents is demonstrated.Comment: This is an extended version of an article to appear in the IEEE Transactions on Automatic Control (additional parts in the Appendix

Examining the Impact of a Consensus Approach to Content Alignment Studies

Although both content alignment and standard-setting procedures rely on content-expert panel judgements, only the latter employs discussion among panel members. This study employed a modified form of the Webb methodology to examine content alignment for twelve tests administered as part of the Massachusetts Comprehensive Assessment System (MCAS). This modification required panel members to discuss items for which there was no consensus regarding the item’s depth of knowledge or targeted standard. After the discussion, panel members were allowed to change their original ratings. The number of changes that occurred were analyzed considering the number of items discussed and the size of the panel. Moreover, we evaluated the impact these changes had on the overall judgments of alignment as reported by Webb’s Web Alignment Tool (WAT). Findings suggest that discussion among panel members between rating rounds positively increased agreement among panel members’ ratings but had minimal effects on the overall judgments of content alignment for 11 of the 12 tests evaluated

Men,Women, and the Ballot – Woman Suffrage in the United States

Woman suffrage led to the greatest enfranchisement in the history of the United States. BeforeWorldWar I, however, suffrage states remained almost exclusively confined to the American West. The reasons for this pioneering role of theWest are still unclear. Studying the timing of woman suffrage adoption at state level, we find that states in which women were scarce (the West) enfranchised their women much earlier than states in which the sex ratio was more balanced (the rest of the country). High sex ratios in the West, that is high ratios of grantors to grantees, reduced the political costs and risks to male electorates and legislators of extending the franchise. They are also likely to have enhanced female bargaining power and may have made woman suffrage more attractive in the eyes of western legislators that sought to attract more women to their states. Our finding of a reduced-form inverse relationship between the relative size of a group and its success in securing the ballot may be of use also for the study of other franchise extensions and for inquieries into the dynamics of political power sharing more generally.Woman suffrage, democratization, political economy, sex ratio