Practical characterization of quantum devices without tomography

Quantum tomography is the main method used to assess the quality of quantum information processing devices, but its complexity presents a major obstacle for the characterization of even moderately large systems. The number of experimental settings required to extract complete information about a device grows exponentially with its size, and so does the running time for processing the data generated by these experiments. Part of the problem is that tomography generates much more information than is usually sought. Taking a more targeted approach, we develop schemes that enable (i) estimating the fidelity of an experiment to a theoretical ideal description, (ii) learning which description within a reduced subset best matches the experimental data. Both these approaches yield a significant reduction in resources compared to tomography. In particular, we demonstrate that fidelity can be estimated from a number of simple experimental settings that is independent of the system size, removing an important roadblock for the experimental study of larger quantum information processing units.Comment: (v1) 11 pages, 1 table, 4 figures. (v2) See also the closely related work: arXiv:1104.4695 (v3) method extended to continuous variable systems (v4) updated to published versio

The Intersection of Politics and Theology: Reading Augustine in Light of Augustine

Augustine’s The City of God is a foundational theological text for the development of Christian thought across time. Over the centuries, political scientists and theologians have been especially interested in this text in a variety of ways, but for the purposes of this discussion, the focus will be on Books I-V and Book XIX. Typically, theologians have been interested in Augustine’s rebuttal of pagan claims that are found in the first five books, while political scientists focus most of their attention on Book XIX for its discussion of the highest ends of the state through the means of politics in a context characterized by fallen humanity. Studying the arguments set forth in these two sections independently of one another has proved to produce valuable additions to both theological and political science scholarship; however, by ignoring the other sections, scholars will have a limited understanding of Augustine’s view on the highest good. It is essential to read Books I-V and Book XIX in light of one another because Augustine is filling in the gaps in his own arguments; because The City of God was a work that was developed over thirteen years, it is absolutely necessary for theologians and political scientists to have read both portions of the text, so they are able to understand the full meaning of Augustine’s completed arguments

Civic Engagement Of Community College Students: A Qualitative Research Study On Community College Curriculum And Civic Engagement

Social scientists claim young United States (U.S.) citizens have become disengaged in civic life which jeopardizes democracy (White et al., 2007; CIRCLE & Carnegie, 2003, p.8). As a nation, the U.S. has failed to teach students the skills, knowledge, and abilities necessary for democratic life (White et l., 2007). Social scientists claim young U.S. citizens have become disengaged in civic life since the 1980s (Colby, 2007; CIRCLE & Carnegie, 2003, p.4). Compared to past generations, young citizens in the United States are less engaged in political life and lack an understanding of what it means to be an active and engaged citizen (Colby, 2007; White et al., 2007; CIRCLE & Carnegie, 2003, p.4). The idea of engaged citizenship has become narrowly defined as the simple act of voting, limiting the possibilities of citizens in improving society through community involvement (White et al., 2007). However, social scientists and social science educators have witnessed an increase in volunteerism of young U.S. citizens since about 2000. Along with this increase in volunteerism, other empirical evidence has painted a more positive picture of young Americans’ civic engagement (Zukin et al., 2006). While researchers admit that young U.S. citizens are less politically engaged, young citizens demonstrate an interest in civic engagement (e.g., volunteering and participating in social campaigns) (Zukin et al., 2006). Historically, kindergarten through twelfth-grade (K-12) social-studies education has responded, through a civic-focused curriculum, to the needs of the United States. The nation’s colleges and universities have also traditionally focused on the education of the country’s future civic leaders, paying particular attention to teaching citizenship for the common good while iv promoting civic duty and responsibility. In comparison, little attention has been focused on the civic education of the community college student. The primary focus of community colleges has been to stimulate local economies and provide training for workforce development. In addition to workforce development, community colleges have provided access to under-prepared students who are interested in completing a four-year degree at a university, where civic leadership has been integrated into the curriculum. This research study followed a qualitative phenomenological approach that investigated the attitudes and perceptions of community college students and their civic and political engagement. The researcher collected data pertaining to civic engagement from three sources: open-ended qualitative questionnaires, student focus-groups, and a drawing activity completed by students. This research study was conducted in a large urban community college located in the southeastern region of the United States. Wilson Community College is a pseudonym used to conceal the identity of the college that was used in this research stud

Recycling Made Easy: An Ergonomic Approach to Home Recycling and Trash Containers

The purpose of this project is to create an ergonomically sound recycling/trash container, with the ultimate hope of making the recycling process easier and more intuitive, thereby increasing recycling rates. Currently, while there are many recycling/trash containers available for purchase, there is no product that has a design without glaring ergonomic flaws. An ergonomic design and product prototype was created as a part of this project, and was subsequently tested against a conventional prototype model. The data collected from the experiments conducted suggests that the new ergonomic model makes the waste disposal process and the container transportation process easier, while two-thirds of participants said that they would be more likely to recycle if they were to own the ergonomic model over the generic. Combined with economic analysis showing the need for a family of four to increase recycling rates by a mere 3% over the course of a year for the economy to see a full payback on the $50 purchase price, government assistance is recommended for consumers looking to acquire this product

Finding Music in Chaos: Designing and Composing with Virtual Instruments Inspired by Chaotic Equations

Using chaos theory to design novel audio synthesis engines has been explored little in computer music. This could be because of the difficulty of obtaining harmonic tones or the likelihood of chaos-based synthesis engines to explode, which then requires re-instantiating of the engine to proceed with sound production. This process is not desirable when composing because of the time wasted fixing the synthesis engine instead of the composer being able to focus completely on the creative aspects of composition. One way to remedy these issues is to connect chaotic equations to individual parts of the synthesis engine instead of relying on the chaos as the primary source of all sound-producing procedures. To do this, one can create a physically-based synthesis model and connect chaotic equations to individual parts of the model. The goal of this project is to design a physically-inspired virtual instrument based on a conceptual percussion instrument model that utilizes chaos theory in the synthesis engine to explore novel sounds in a reliable and repeatable way for other composers and performers to use. This project presents a two-movement composition utilizing these concepts and a modular set of virtual instruments that can be used by anyone, which can be interacted with by a new electronic music controller called the Hexapad controller and standard MIDI controllers. The physically-inspired instrument created for the Hexapad controller is called the Ambi-Drum and standard MIDI controllers are used to control synthesis parameters and other virtual instruments

Understanding the High Attrition Rates of Male Collegiate Basketball Student-Athletes

The purpose of this applied study was to gain a better understanding of the high attrition rates among male collegiate basketball student-athletes and to recommend practices that institutions can implement to address and solve this increasing problem. The study utilized a multimethod approach and collected data through a series of interviews, a focus group, and a survey. Based on the results of the data, a series of recommendations have been included to address the high attrition rates among male collegiate basketball student-athletes. Most of the recommendations are based on how the recruiting process can be better handled by representatives of the institutions as well as by the potential student-athletes that are being recruited. Additional recommendations are based on Tinto’s theory of departure, which states that a student who is integrated and involved with a community is more likely to be retained

Socially Constructing God: Gender, Culture, and a Stratified Trinity

The Problem. Both hierarchicalist and equivalentist evangelicals use Trinitarian relations to argue for their opposing views on gender roles. How can this stalemate be broken if the Bible, the typical evangelical foundation for resolving doctrinal disputes, is used by both sides to argue their contrasting positions? -- Methods and Procedures. I explored the cultural determination of worldview, bringing the fields of sociology, psychology, history, and philosophy to bear on this theological debate and considered whether it may be differing presuppositions and subsequent opposing interpretations that cause the conflicting positions, rather than what the biblical text means. By looking through the eyes of experts in this mix of fields, I gained insight on the development and impact of gender presuppositions in regard to role stratification in the conceptualization of the Trinity. -- Findings. I found that culturally determined presuppositions seem to be at the root of the disagreement. It would seem that the divine is being conceptualized and stratified according to contemporary human society. Until each side of the debate can understand their presuppositions and recognize the extent to which they are creating God in their image, constructive dialogue will be limited and I project that the debate will continue passionately and divisively

Stability of Vortex Solutions to an Extended Navier-Stokes System

We study the long-time behavior an extended Navier-Stokes system in $\R^2$ where the incompressibility constraint is relaxed. This is one of several "reduced models" of Grubb and Solonnikov '89 and was revisited recently (Liu, Liu, Pego '07) in bounded domains in order to explain the fast convergence of certain numerical schemes (Johnston, Liu '04). Our first result shows that if the initial divergence of the fluid velocity is mean zero, then the Oseen vortex is globally asymptotically stable. This is the same as the Gallay Wayne '05 result for the standard Navier-Stokes equations. When the initial divergence is not mean zero, we show that the analogue of the Oseen vortex exists and is stable under small perturbations. For completeness, we also prove global well-posedness of the system we study.Comment: 24 pages, 1 figure, updated to add authors' contact information and to address referee's comment

Decoherence suppression via environment preparation

To protect a quantum system from decoherence due to interaction with its environment, we investigate the existence of initial states of the environment allowing for decoherence-free evolution of the system. For models in which a two-state system interacts with a dynamical environment, we prove that such states exist if and only if the interaction and self-evolution Hamiltonians share an eigenstate. If decoherence by state preparation is not possible, we show that initial states minimizing decoherence result from a delicate compromise between the environment and interaction dynamics.Comment: 4 pages, 2 figure