Complete Separability and Fourier representations of n-qubit states

Necessary conditions for separability are most easily expressed in the computational basis, while sufficient conditions are most conveniently expressed in the spin basis. We use the Hadamard matrix to define the relationship between these two bases and to emphasize its interpretation as a Fourier transform. We then prove a general sufficient condition for complete separability in terms of the spin coefficients and give necessary and sufficient conditions for the complete separability of a class of generalized Werner densities. As a further application of the theory, we give necessary and sufficient conditions for full separability for a particular set of $n$-qubit states whose densities all satisfy the Peres condition

Mutually Unbiased Bases, Generalized Spin Matrices and Separability

A collection of orthonormal bases for a complex dXd Hilbert space is called mutually unbiased (MUB) if for any two vectors v and w from different bases the square of the inner product equals 1/d: || ^{2}=1/d. The MUB problem is to prove or disprove the the existence of a maximal set of d+1 bases. It has been shown in [W. K. Wootters, B. D. Fields, Annals of Physics, 191, no. 2, 363-381, (1989)] that such a collection exists if d is a power of a prime number p. We revisit this problem and use dX d generalizations of the Pauli spin matrices to give a constructive proof of this result. Specifically we give explicit representations of commuting families of unitary matrices whose eigenvectors solve the MUB problem. Additionally we give formulas from which the orthogonal bases can be readily computed. We show how the techniques developed here provide a natural way to analyze the separability of the bases. The techniques used require properties of algebraic field extensions, and the relevant part of that theory is included in an Appendix

Effects of mismatched transmissions on two-mode squeezing and EPR correlations with a slow light medium

We theoretically discuss the preservation of squeezing and continuous variable entanglement of two mode squeezed light when the two modes are subjected to unequal transmission. One of the modes is transmitted through a slow light medium while the other is sent through an optical fiber of unit transmission. Balanced homodyne detection is used to check the presence of squeezing. It is found that loss of squeezing occurs when the mismatch in the transmission of the two modes is greater than 40% while near ideal squeezing is preserved when the transmissions are equal. We also discuss the effect of this loss on continuous variable entanglement using strong and weak EPR criteria and possible applications for this experimental scheme.Comment: 7 pages, 4 figure

A religious program for a Christian arts college

Thesis (Ed.M.)--Boston Universit

PROGRAMMED EFFECTS OF SURFACE WATER PRICE LEVELS ON U.S. AGRICULTURAL WATER USE AND PRODUCTION PATTERNS

Resource /Energy Economics and Policy,

PPP Strikes Back: Aggregation and the Real Exchange Rate

We show the importance of a dynamic aggregation bias in accounting for the PPP puzzle. We prove that established time series and panel methods substantially exaggerate the persistence of real exchange rates because of heterogeneity in the dynamics of disaggregated relative prices. When heterogeneity is properly taken into account, estimates of the real exchange rate half-life fall dramatically, to little more than one year, or significantly below Rogoff's consensus view' of three to five years. We show corrected estimates are consistent with plausible nominal rigidities, thus, arguably, solving the puzzle. We also explain why traded goods prices account for the bulk of the persistence and volatility of the real exchange rate. The reason is that traded goods prices display dynamics that are more heterogeneous than non-traded ones.

A Cross-Cultural Perspective on Selected Mental Health Systems

The information provided from authors around the world on their respective mental health systems is analyzed and compared. Several key dimensions are utilized, including the relationship of mental health services to other services, institutional care, community care, staffing, prevention and mental health promotion services, and accessibility. Resources and governmental priorities are identified as being essential to the provision of effective services. It is clear that the general trends identified by the experts for mental health in both developing and developed countries are by no means universal in applicability

What is the best macrolide for atypical pneumonia?

Erythromycin, clarithromycin, and azithromycin are equally effective in treating pneumonia caused by Mycoplasma pneumoniae or Chlamydophila (formerly Chlamydia) pneumoniae (strength of recommendation [SOR]: B, small head-to-head trials). Macrolide choice can be based on other considerations--cost, side effects, and effectiveness against other suspected pathogens (SOR: C, expert opinion)