On the determination of near body orbits using mass concentration models

Mathematical model for near-body orbit calculation using mass concentration, perturbation theory, nonlinear equations, geopotentials, and least squares metho

Inverse problems in partial differential equations

Identification in partial differential equations by Laplace equatio

DELINEATION OF TRACKS OF HEAVY COSMIC RAYS AND NUCLEAR PROCESSES WITHIN LARGE SILVER CHLORIDE CRYSTALS

Delineation of tracks of heavy cosmic rays and nuclear processes with in large silver chloride crystal

Using Quantum Computers for Quantum Simulation

Numerical simulation of quantum systems is crucial to further our understanding of natural phenomena. Many systems of key interest and importance, in areas such as superconducting materials and quantum chemistry, are thought to be described by models which we cannot solve with sufficient accuracy, neither analytically nor numerically with classical computers. Using a quantum computer to simulate such quantum systems has been viewed as a key application of quantum computation from the very beginning of the field in the 1980s. Moreover, useful results beyond the reach of classical computation are expected to be accessible with fewer than a hundred qubits, making quantum simulation potentially one of the earliest practical applications of quantum computers. In this paper we survey the theoretical and experimental development of quantum simulation using quantum computers, from the first ideas to the intense research efforts currently underway.Comment: 43 pages, 136 references, review article, v2 major revisions in response to referee comments, v3 significant revisions, identical to published version apart from format, ArXiv version has table of contents and references in alphabetical orde

Universal quantum computation by discontinuous quantum walk

Quantum walks are the quantum-mechanical analog of random walks, in which a quantum `walker' evolves between initial and final states by traversing the edges of a graph, either in discrete steps from node to node or via continuous evolution under the Hamiltonian furnished by the adjacency matrix of the graph. We present a hybrid scheme for universal quantum computation in which a quantum walker takes discrete steps of continuous evolution. This `discontinuous' quantum walk employs perfect quantum state transfer between two nodes of specific subgraphs chosen to implement a universal gate set, thereby ensuring unitary evolution without requiring the introduction of an ancillary coin space. The run time is linear in the number of simulated qubits and gates. The scheme allows multiple runs of the algorithm to be executed almost simultaneously by starting walkers one timestep apart.Comment: 7 pages, revte

Searches on star graphs and equivalent oracle problems

We examine a search on a graph among a number of different kinds of objects (vertices), one of which we want to find. In a standard graph search, all of the vertices are the same, except for one, the marked vertex, and that is the one we wish to find. We examine the case in which the unmarked vertices can be of different types, so the background against which the search is done is not uniform. We find that the search can still be successful, but the probability of success is lower than in the uniform background case, and that probability decreases with the number of types of unmarked vertices. We also show how the graph searches can be rephrased as equivalent oracle problems

Application of DOT-MORSE coupling to the analysis of three-dimensional SNAP shielding problems

The use of discrete ordinates and Monte Carlo techniques to solve radiation transport problems is discussed. A general discussion of two possible coupling schemes is given for the two methods. The calculation of the reactor radiation scattered from a docked service and command module is used as an example of coupling discrete ordinates (DOT) and Monte Carlo (MORSE) calculations

Serving Exoticism: The Black Female in French Exotic Imagery, 1733-1885

The black female played an important part in the construction of exotic female sexuality in French painting for nearly two hundred years, yet her symbolic complexity has not been fully explored. This thesis is a contextual analysis of the image of the black female in French painting from the early part of the eighteenth through the nineteenth century. Representations of black females in this era are part of the larger development of turquerie in the eighteenth century and Orientalism in the nineteenth century. Centered around European fantasies of Near Eastern and North African harem culture, turquerie and Orientalism provided an exotic framework in which issues of female sexuality and its relationship to race was explored. The objects discussed in this thesis, primarily well known works by academic painters, are examples of images in which the black female plays a significant stylistic and ideological role. The works are examined in relation to literary and scientific discourses in which ideas about black women were negotiated during the period. Slavery, imperialism, as well as colonial expansion contextualize the imagery, and offer tools with which to uncover encoded meanings inscribed in the exoticized black female. This analysis provides an expanded definition of the nature of the black female as a symbol, and outlines a complex, multidimensional framework in which black female figures operate as a sexual signifier

Doctor of Philosophy

dissertationWe analyze different models of several chemical reactions. We find that, for some reactions, the steady state behavior of the chemical master equation, which describes the continuous time, discrete state Markov process, is poorly approximated by the deterministic model derived from the law of mass action or a mean field model derived in a similar way. We show that certain simple enzymatic reactions have bimodal stationary distributions in appropriate parameter ranges, though the deterministic and mean field models for these reactions do not have the capacity to admit multiple equilibrium points no matter the choice of rate constants. We provide power series expansions for these bimodal distributions. We also consider several variants of an autocatalytic reaction. This reaction's deterministic model predicts a unique positive stable equilibrium, but the only stationary distribution of its chemical master equation predicts extinction of the autocatalytic chemical species with probability 1. We show that the transient distribution of this chemical master equation is centered near the deterministic equilibrium and that the stationary distribution is only reached on a much longer time scale. Finally, we consider a model for the rotational direction switching of the bacterial rotary motor and propose two possible reductions for the state space of the corresponding Markov chain. One reduction, a mean field approximation, is unable to produce physically realistic phenomena. The other reduction retains the properties of interest in the system while significantly decreasing the computation required for analysis. We use this second reduction to fit parameters for the full stochastic system and suggest a mechanism for the sensitivity of the switch

Distinguishing n Hamiltonians on C^n by a single measurement

If an experimentalist wants to decide which one of n possible Hamiltonians acting on an n dimensional Hilbert space is present, he can conjugate the time evolution by an appropriate sequence of known unitary transformations in such a way that the different Hamiltonians result in mutual orthogonal final states. We present a general scheme providing such a sequence.Comment: 4 pages, Revte