Automorphism groupoids in noncommutative projective geometry

We address a natural question in noncommutative geometry, namely the rigidity observed in many examples, whereby noncommutative spaces (or equivalently their coordinate algebras) have very few automorphisms by comparison with their commutative counterparts. In the framework of noncommutative projective geometry, we define a groupoid whose objects are noncommutative projective spaces of a given dimension and whose morphisms correspond to isomorphisms of these. This groupoid is then a natural generalization of an automorphism group. Using work of Zhang, we may translate this structure to the algebraic side, wherein we consider homogeneous coordinate algebras of noncommutative projective spaces. The morphisms in our groupoid precisely correspond to the existence of a Zhang twist relating the two coordinate algebras. We analyse this automorphism groupoid, showing that in dimension 1 it is connected, so that every noncommutative $\mathbb{P}^{1}$ is isomorphic to commutative $\mathbb{P}^{1}$. For dimension 2 and above, we use the geometry of the point scheme, as introduced by Artin-Tate-Van den Bergh, to relate morphisms in our groupoid to certain automorphisms of the point scheme. We apply our results to two important examples, quantum projective spaces and Sklyanin algebras. In both cases, we are able to use the geometry of the point schemes to fully describe the corresponding component of the automorphism groupoid. This provides a concrete description of the collection of Zhang twists of these algebras.Comment: 27 pages; v2: minor corrections and additional reference

The flute as imitator and as the most imitated of instruments

Thesis (M.M.)--Boston Universit

The Proposed U.S.-South Korea Free Trade Agreement (KORUS FTA): Provisions and Implications

On June 30, 2007, United States Trade Representative Susan Schwab and South Korean Foreign Trade Minister Kim Hyung-chong signed the proposed U.S.-South Korean Free Trade Agreement (KORUS FTA) for their respective countries. If approved, the KORUS FTA would be the largest FTA that South Korea has signed to date and would be the second largest (next to North American Free Trade Agreement NAFTA) in which the United States participates. South Korea is the seventh-largest trading partner of the United States and the United States is South Korea’s third largest trading partner. Various studies conclude that the agreement would increase bilateral trade and investment flows. The final text of the proposed KORUS FTA covers a wide range of trade and investment issues and, therefore, could have wide economic implications for both the United States and South Korea. The KORUS FTA includes issues on which the two countries achieved early agreement, such as the elimination on tariffs on trade in most manufactured goods and the partial liberalization in services trade. The agreement also includes provisions on a number of very sensitive issues, such as autos, agriculture, and trade remedies, on which agreement was reached only during the final hours of negotiations. If the agreement is to enter into force, Congress will have to approve implementation legislation. The negotiations were conducted under the trade promotion authority (TPA), also called fast-track trade authority, that the Congress granted the President under the Bipartisan Trade Promotion Act of 2002 (P.L. 107-210). The authority allows the President to enter into trade agreements that receive expedited congressional consideration (no amendments and limited debate). The White House has not indicated when it will send the draft implementing legislation to Congress. (The TPA sets no deadline for the President to do this.) While a broad swath of the U.S. business community supports the agreement, the KORUS FTA faces opposition from some groups, including some auto and steel manufacturers and labor unions. In addition, the agricultural community and some Members of Congress have withheld support for the agreement until South Korea lifts its restrictions on imports of U.S. beef. Some U.S. supporters view passage of the KORUS FTA as important to secure new opportunities in the South Korea market. Opponents claim that the KORUS FTA does not go far enough in opening up the South Korean market and is a lost opportunity to resolve long running concerns about South Korean barriers. Other observers have suggested the outcome of the KORUS FTA could have implications for the U.S.-South Korean alliance as a whole. Differences between the White House and the Democratic leadership in the Congress over the implications of the KORUS FTA have made the timing and even the likelihood of the President’s submission and the Congress’s subsequent consideration of implementing legislation uncertain. This report will be updated as events warrant

Relieving Human Suffering: Compassion in Social Policy

Human suffering is always present in society. There is general consensus that action should be taken to address suffering, but there are differing views as to the appropriate means of doing so. In this paper we utilize a classical understanding of the virtue of compassion to answer the research question: How does contemporary U.S. policy address human suffering through compassionate response? To answer this question, we conduct a critical analysis of three policy domains (hospice care, domestic violence, and disaster relief) to determine variation in response to human suffering. Comparisons among the domains suggest the various ways in which compassion can be observed within formal social policy. We discuss the implications of a compassion-focused approach to analysis of policies that address human suffering, and more broadly, the use of a virtue-oriented perspective on policy

Construction and evaluation of group tests in reading for grades one, two, and three.

Thesis (Ed.M.)--Boston Universit

Developing a Student Employee Leadership Program: The Importance of Evaluating Effectiveness

Outstanding student employees are essential for campus recreation programs to achieve organizational goals. To that end, this study examined the effectiveness of a leadership development program in which three groups of campus recreation (rec sports) student employees participated at various levels in the following: oncampus training, an off-site retreat, a scavenger hunt, and biweekly meetings. Using a quasi-experimental design, data were collected in two phases from 51 students and measured the growth of each student’s leadership capabilities as reported using the Student Leadership Practices Inventory. Statistical analyses revealed that group membership did significantly affect growth in the student’s leadership capacity, F(2, 48) = 7.07, p = .002, η2 = .228. Campus recreation programs are increasingly held accountable and rec sports professionals must understand assessment is vital. The results of this study reveal that rec sports professionals can impact the development of student leaders. Specifically, the findings indicate that growth does not occur with condensed training. Indeed lasting, meaningful growth transpires only when leadership lessons are embedded using a sustained approach. Implications for research and practice are presented

Tunable Narrow Band Difference Frequency THz Wave Generation in DAST via Dual Seed PPLN OPG

We report a widely tunable narrowband terahertz (THz) source via difference frequency generation (DFG). A narrowband THz source uses the output of dual seeded periodically poled lithium niobate (PPLN) optical parametric generators (OPG) combined in the nonlinear crystal 4-dimthylamino-N-methyl-4-stilbazolium-tosylate (DAST). We demonstrate a seamlessly tunable THZ output that tunes from 1.5 THz to 27 THz with a minimum bandwidth of 3.1 GHz. The effects of dispersive phase matching, two-photon absorption, and polarization were examined and compared to a power emission model that consisted of the current accepted parameters of DAST