Proposed experiments to probe the non-abelian \nu=5/2 quantum Hall state

We propose several experiments to test the non-abelian nature of quasi-particles in the fractional quantum Hall state of \nu=5/2. One set of experiments studies interference contribution to back-scattering of current, and is a simplified version of an experiment suggested recently. Another set looks at thermodynamic properties of a closed system. Both experiments are only weakly sensitive to disorder-induced distribution of localized quasi-particles.Comment: Additional references and an improved figure, 5 page

Switching noise as a probe of statistics in the fractional quantum Hall effect

We propose an experiment to probe the unconventional quantum statistics of quasi-particles in fractional quantum Hall states by measurement of current noise. The geometry we consider is that of a Hall bar where two quantum point contacts introduce two interfering amplitudes for back-scattering. Thermal fluctuations of the number of quasi-particles enclosed between the two point contacts introduce current noise, which reflects the statistics of the quasi-particles. We analyze abelian $\nu=1/q$ states and the non-abelian $\nu=5/2$ state

Characteristics of a future aeronautical satellite communications system

A possible operational system scenario for providing satellite communications services to the future aviation community was analyzed. The system concept relies on a Ka-band (20/30 GHz) satellite that utilizes multibeam antenna (MBA) technology. The aircraft terminal uses an extremely small aperture antenna as a result of using this higher spectrum at Ka-band. The satellite functions as a relay between the aircraft and the ground stations. The ground stations function as interfaces to the existing terrestrial networks such as the Public Service Telephone Network (PSTN). Various system tradeoffs are first examined to ensure optimized system parameters. High level performance specifications and design approaches are generated for the space, ground, and aeronautical elements in the system. Both technical and economical issues affecting the feasibility of the studied concept are addressed with the 1995 timeframe in mind

Empirical modeling of the quiet time nightside magnetosphere

Empirical modeling of plasma pressure and magnetic field for the quiet time nightside magnetosphere is investigated. Two models are constructed for this study. One model, referred to here as T89R, is basically the magnetic field model of Tsyganenko (1989) but is modified by the addition of an inner eastward ring current at a radial distance of ∼3 RE as suggested by observation. The other is a combination of the T89R model and the long version of the magnetic field model of Tsyganenko (1987) such that the former dominates the magnetic field in the inner magnetosphere, whereas the latter prevails in the distant tail. The distribution of plasma pressure, which is required to balance the magnetic force for each of these two field models, is computed along the tail axis in the midnight meridian. The occurrence of pressure anisotropy in the inner magnetospheric region is also taken into account by determining an empirical fit to the observed plasma pressure anisotropy. This effort is the first attempt to obtain the plasma pressure distribution in force equilibrium with magnetic stresses from an empirical field model with the inclusion of pressure anisotropy. The inclusion of pressure anisotropy alters the plasma pressure by as much as a factor of ∼3 in the inner magnetosphere. The deduced plasma pressure profile along the tail axis is found to be in good agreement with the observed quiet time plasma pressure for geocentric distances between ∼2 and ∼35 RE

Spitzer Constraints on the z=6.56 Galaxy Lensed by Abell 370

We report on Spitzer IRAC observations of the spectroscopically confirmed z=6.56 lensed Ly-alpha emitting source HCM 6A which was found behind the cluster Abell 370. Detection of the source at 3.6 and 4.5 microns, corresponding to rest-frame optical emission, allows us to study the stellar population of this primeval galaxy. The broadband flux density at 4.5 microns is enhanced compared to the continuum at other wavelengths, likely due to the presence of strong H-alpha in emission. The derived H-alpha line flux corresponds to a star-formation rate of around 140 M_{sun}/yr, more than an order of magnitude larger than estimates from the ultraviolet continuum and Ly-alpha emission line. The dust extinction required to explain the discrepancy is A_V of about 1 mag. The inference of dust at such high redshifts is surprising and implies that the first epoch of star-formation in this galaxy occurred at z~20.Comment: 11 pages, 3 figures, ApJ Letters in pres

Juncture stress fields in multicellular shell structures. Volume IV - Stresses and deformations of fixed-edge segmental spherical shells Final report

Equations for thin elastic spherical shells and digital program for analysis of stresses and deformation of fixed edge segmental spherical shells - solution by finite difference techniqu

Juncture stress fields in multicellular shell structures. Volume III - Stresses and deformations on fixed-edge segmental conical shells Final report

Equations for thin elastic conical shells and digital program for analysis of stress and deformation on fixed edge segmental conical shells - solution by finite difference techniqu

Property\u27s Constitution

Long-standing disagreements over the definition of property as a matter of legal theory present a special problem in constitutional law. The Due Process and Takings Clauses establish individual rights that can be asserted only if “property” is at stake. Yet the leading cases interpreting constitutional property doctrines have never managed to articulate a coherent general view of property, and in some instances have reached opposite conclusions about its meaning. Most notably, government benefits provided in the form of individual legal entitlements are considered “property” for purposes of due process but not takings doctrines, a conflict the cases acknowledge but do not attempt to explain. This Article offers a way to bring order to the confused treatment of property in constitutional law. It shows how a single definition of property can be adopted for all of the major constitutional property doctrines without the calamitous results that many seem to fear. The Article begins by arguing that property is best understood as the right to have some measure of legal control over the way a particular item is used, control that comes at the expense of all other people. It then argues that legal rights are a kind of private property, and that while courts and commentators can validly invoke property in the context of legal entitlements to government benefits—so-called new property—they mistakenly believe the property at issue is the good a recipient has a right to receive, rather than the legal right to receive it. The Article shows that legal rights are the only category of things whose existence government can altogether extinguish. For this reason, ownership of legal rights is the only kind of property right government can terminate without conferring equivalent property rights on others. The Article further argues that while due process protection should apply whenever a person is denied an asserted property right (a deprivation), takings protection should only come into play when property rights are transferred from one party to another (a taking). Combining these observations, the Article concludes that termination of both “new property” rights and old-fashioned in personam legal rights should trigger due process but not takings protection. This analysis provides theoretical coherence that constitutional doctrine currently lacks. It also sheds light on the essential characteristics of property rights as a general matter, in order to help theoreticians understand more clearly the core structures of property law