Photoemission study of the electronic structure of CdTe

Photoemission study of electronic structure of cadmium telluride single crystal

A new construction for a QMA complete 3-local Hamiltonian

We present a new way of encoding a quantum computation into a 3-local Hamiltonian. Our construction is novel in that it does not include any terms that induce legal-illegal clock transitions. Therefore, the weights of the terms in the Hamiltonian do not scale with the size of the problem as in previous constructions. This improves the construction by Kempe and Regev, who were the first to prove that 3-local Hamiltonian is complete for the complexity class QMA, the quantum analogue of NP. Quantum k-SAT, a restricted version of the local Hamiltonian problem using only projector terms, was introduced by Bravyi as an analogue of the classical k-SAT problem. Bravyi proved that quantum 4-SAT is complete for the class QMA with one-sided error (QMA_1) and that quantum 2-SAT is in P. We give an encoding of a quantum circuit into a quantum 4-SAT Hamiltonian using only 3-local terms. As an intermediate step to this 3-local construction, we show that quantum 3-SAT for particles with dimensions 3x2x2 (a qutrit and two qubits) is QMA_1 complete. The complexity of quantum 3-SAT with qubits remains an open question.Comment: 11 pages, 4 figure

Solidarity and salvation : the relationship between personal transformation and community in Dietrich Bonhoeffer

The major thesis of this dissertation is that personal transformation is grounded in community existence and experience. Bonhoeffer's understanding and experience of community provide key insights into this dynamic relationship. The development of his theology, shaped by his experience of struggle and solidarity in Nazi Germany, can also provide valuable resources for the struggle for justice and peace in South Africa, especially at this transitionary period in its history. The first chapter, A Theoretical Perspective: Sociality in Sanctorum Cornmunio and Creation and Fall, attempts to establish the theoretical underpinnings and centrality of Bonhoeffer's notion of 'sociality' which, it is argued, remains at the heart of his writings and praxis to the end of his life. It is in the concept of sociality that the influence of community on personal transformation is grounded. The second chapter, Reflections on Life in Community: Discipleship and Community in The Cost of Discipleship and Life Together, examines key issues at the heart of Bonhoeffer' s struggle for justice based in the concrete experience of intentional community life at the Finkenwalde seminary. In the context of the Church Struggle (Kirchenkampf) the community of faith was integral to helping pastors be obedient disciples in the midst of tremendous political struggles with an evil regime. The third chapter, A Vision - The Church for Others: Suffering, Metanoia and Responsibility in Ethics and Letters and Papers from Prison, explores the implications of personal transformation for a life of responsible discipleship. There is continuity in Bonhoeffer's thinking about personal transformation and community, but his context had changed during this period resulting in more emphasis on involvement in 'the world' and taking responsibility for changing the world

The Uptake of Calcium by ISO Lines and Kentucky Varieties of Nicotiana Tabacum L.

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Francis J. Shay on July 18, 1968

Super-Alfv\'enic propagation of reconnection signatures and Poynting flux during substorms

The propagation of reconnection signatures and their associated energy are examined using kinetic particle-in-cell simulations and Cluster satellite observations. It is found that the quadrupolar out-of-plane magnetic field near the separatrices is associated with a kinetic Alfv\'en wave. For magnetotail parameters, the parallel propagation of this wave is super-Alfv\'enic (V_parallel ~ 1500 - 5500 km/s) and generates substantial Poynting flux (S ~ 10^-5 - 10^-4 W/m^2) consistent with Cluster observations of magnetic reconnection. This Poynting flux substantially exceeds that due to frozen-in ion bulk outflows and is sufficient to generate white light aurora in the Earth's ionosphere.Comment: Submitted to PRL on 11/1/2010. Resubmitted on 4/5/201

Transition from ion-coupled to electron-only reconnection: Basic physics and implications for plasma turbulence

Using kinetic particle-in-cell (PIC) simulations, we simulate reconnection conditions appropriate for the magnetosheath and solar wind, i.e., plasma beta (ratio of gas pressure to magnetic pressure) greater than 1 and low magnetic shear (strong guide field). Changing the simulation domain size, we find that the ion response varies greatly. For reconnecting regions with scales comparable to the ion Larmor radius, the ions do not respond to the reconnection dynamics leading to ''electron-only'' reconnection with very large quasi-steady reconnection rates. The transition to more traditional ''ion-coupled'' reconnection is gradual as the reconnection domain size increases, with the ions becoming frozen-in in the exhaust when the magnetic island width in the normal direction reaches many ion inertial lengths. During this transition, the quasi-steady reconnection rate decreases until the ions are fully coupled, ultimately reaching an asymptotic value. The scaling of the ion outflow velocity with exhaust width during this electron-only to ion-coupled transition is found to be consistent with a theoretical model of a newly reconnected field line. In order to have a fully frozen-in ion exhaust with ion flows comparable to the reconnection Alfv\'en speed, an exhaust width of at least several ion inertial lengths is needed. In turbulent systems with reconnection occurring between magnetic bubbles associated with fluctuations, using geometric arguments we estimate that fully ion-coupled reconnection requires magnetic bubble length scales of at least several tens of ion inertial lengths

Axions Scattering From a Quadrupole Magnetic Field

We study the 2D scattering of axions from an accelerator like quadrupole magnet using the eikonal approximation in order to learn whether or not such a setup could serve as a new possible method for detecting axions on terrestrial experiments. The eikonal approximation in 2D is introduced and explained. We also apply the eikonal approximation to two known cases in order to compare it with previous results, obtained using Born's approximation, and discuss its correctness

Spectroscopic Binary Mass Determination using Relativity

High-precision radial-velocity techniques, which enabled the detection of extrasolar planets are now sensitive to relativistic effects in the data of spectroscopic binary stars (SBs). We show how these effects can be used to derive the absolute masses of the components of eclipsing single-lined SBs and double-lined SBs from Doppler measurements alone. High-precision stellar spectroscopy can thus substantially increase the number of measured stellar masses, thereby improving the mass-radius and mass-luminosity calibrations.Comment: 10 pages, 1 figure, accepted for publication by the Astrophysical Journal Letter