Time evolution of open quantum many-body systems

We establish a generic method to analyze the time evolution of open quantum many-body systems. Our approach is based on a variational integration of the quantum master equation describing the dynamics and naturally connects to a variational principle for its nonequilibrium steady state. We successfully apply our variational method to study dissipative Rydberg gases, finding excellent quantitative agreement with small-scale simulations of the full quantum master equation. We observe that correlations related to non-Markovian behavior play a significant role during the relaxation dynamics towards the steady state. We further quantify this non-Markovianity and find it to be closely connected to an information-theoretical measure of quantum and classical correlations.Comment: 5+3 pages, 8 figure

Geologic interpretation of Skylab photographs

There are no author-identified significant results in this report

Toward a multiple mentor model in music education

Literature supports the importance of mentoring relationships in making meaningful contributions to novice teacher induction, and that especially important in the relationship is matching mentor/mentee by subject and grade level and in close proximity. The physical location of mentors to mentees and their availability impacts the relationship. Proximity is necessary to view the mentor as accessible and provide opportunities for interactions during the school day. In music education, matching mentor/mentee by subject and grade level and in close proximity can be challenging. Because of music\u27s specialization, music teachers are often the only one in their building. I previously examined two music teacher mentor/mentee relationships within one stale-wide novice teacher induction program and found that while these pairs were matched by subject and grade level, challenges of time and proximity were evident. The purpose of this paper is to explore a multiple mentoring model in music education; how mentoring could be expanded beyond a one-to-one relationship lo a broader, more collaborative and community-based approach that includes multiple mentors at the school building and district level with a variety of expertise in leaching and subject content area. This model will allow multiple relationships to form to provide novice teachers a support system including a variety of people in close and distant proximity. This model will build off Jacobs\u27 (2008) model for the effective mentoring of music educators, and while ii will focus on music, it can be adapted to fit all subjects

SigTree: A Microbial Community Analysis Tool to Identify and Visualize Significantly Responsive Branches in a Phylogenetic Tree.

Microbial community analysis experiments to assess the effect of a treatment intervention (or environmental change) on the relative abundance levels of multiple related microbial species (or operational taxonomic units) simultaneously using high throughput genomics are becoming increasingly common. Within the framework of the evolutionary phylogeny of all species considered in the experiment, this translates to a statistical need to identify the phylogenetic branches that exhibit a significant consensus response (in terms of operational taxonomic unit abundance) to the intervention. We present the R software package SigTree, a collection of flexible tools that make use of meta-analysis methods and regular expressions to identify and visualize significantly responsive branches in a phylogenetic tree, while appropriately adjusting for multiple comparisons

Long-range quantum gates using dipolar crystals

We propose the use of dipolar spin chains to enable long-range quantum logic between distant qubits. In our approach, an effective interaction between remote qubits is achieved by adiabatically following the ground state of the dipolar chain across the paramagnet to crystal phase transition. We demonstrate that the proposed quantum gate is particularly robust against disorder and derive scaling relations, showing that high-fidelity qubit coupling is possible in the presence of realistic imperfections. Possible experimental implementations in systems ranging from ultracold Rydberg atoms to arrays of Nitrogen-Vacancy defect centers in diamond are discussed.Comment: 5 pages, 3 figure

Multicritical behavior in dissipative Ising models

We analyze theoretically the many-body dynamics of a dissipative Ising model in a transverse field using a variational approach. We find that the steady state phase diagram is substantially modified compared to its equilibrium counterpart, including the appearance of a multicritical point belonging to a different universality class. Building on our variational analysis, we establish a field-theoretical treatment corresponding to a dissipative variant of a Ginzburg-Landau theory, which allows us to compute the upper critical dimension of the system. Finally, we present a possible experimental realization of the dissipative Ising model using ultracold Rydberg gases.Comment: 8 pages, 4 figure

Economics as a conceptual resource for the study of public management

Four related bodies of knowledge inform the study and practice of public management. Broadest in scope is knowledge about the political processes that place demands, provide opportunities, and impose constraints on public managers. Next broadest in scope is policy analysis, which provides the conceptual foundations and craft skills for determining what government should do and how it should be done. Organizational design, a subset of policy analysis, gives insight into how the public sector can be organized to facilitate the effective delivery of goods and services. Narrowest in scope, but most directly relevant to the practice of management, is knowledge about how to carry out executive functions skillfully within existing organizational designs. We take the latter two bodies of knowledge, organizational design and executive function, as the core of the craft and science of public management. In this essay we consider what the discipline of economics offers for research on the core of public management

Introduction to the special issue ‘Integrated scenario building in energy transition research

Adaptive governance approaches emphasize the crucial role of the private sector in enabling climate change adaptation. Yet, the participation of local firms is still lacking, and little is known about the conditions potentially influencing firms’ adaptation decisions and mechanisms that might encourage private sector engagement. We address this gap with an empirical analysis of the willingness of manufacturing small- and medium-sized enterprises (SMEs) to participate financially in collective flood adaptation in Ho Chi Minh City (HCMC), a hotspot of future climate change risk. Using scenario-based field experiments, we shed light on internal and external conditions that influence potential investments in collective initiatives and explain what role SMEs can play in flood adaptation. We find that direct impacts of floods, perceived self-responsibility, and strong local ties motivate firms to participate in collective adaptation, whereas government support, sufficient financial resources, and previously implemented flood protection strategies reduce the necessity to act collectively. Here, opportunity costs and the handling of other business risks play a decisive role in investment decisions. This study shows that although private sector engagement appears to be a promising approach, it is not a panacea. Collective initiatives on flood adaptation need formal guidance and should involve local business networks and partnerships to give voice to the needs and capacities of SMEs, but such initiatives should not overstretch firms’ responsibilities