Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Physics
Gravitationally Induced Quantum Superposition Reduction With Large Extra Dimensions, Jonas R. Mureika
Gravitationally Induced Quantum Superposition Reduction With Large Extra Dimensions, Jonas R. Mureika
Jonas Mureika
A gravity-driven mechanism (``objective reduction'') proposed to explain quantum state reduction is analyzed in light of the possible existence of large extra dimensions in the ADD scenario. By calculating order-of-magnitude estimates for nucleon superpositions, it is shown that if the mechanism at question is correct, constraints may be placed on the number and size of extra dimensions. Hence, measurement of superposition collapse times ({\it e.g.} through diffraction or reflection experiments) could represent a new probe of extra dimensions. The influence of a time-dependent gravitational constant on the gravity-driven collapse scheme with and without the presence of extra dimensions is also …
Development Without Energy? Assessing Future Scenarios Of Energy Consumption In Developing Countries, Jan Steckel, Robert Brecha, Michael Jakob, Jessica Strefler, Gunnar Luderer
Development Without Energy? Assessing Future Scenarios Of Energy Consumption In Developing Countries, Jan Steckel, Robert Brecha, Michael Jakob, Jessica Strefler, Gunnar Luderer
Robert J. Brecha
We analyze the relationship between economic development and energy consumption in the context of greenhouse gas mitigation. The main contribution of this work is to compare estimates of energy thresholds in the form of minimum energy requirements to reach high levels of development with output projections of per capita final energy supply from a group of integrated assessment models (IAMs). Scenarios project that reductions of carbon emissions in developing countries will be achieved not only by means of decreasing the carbon intensity, but also by making a significant break with the historically observed relationship between energy use and economic growth. …
Finite Molecular Anchoring In The Escaped-Radial Nematic Configuration: A 2-H-Nmr Study, G. P. Crawford, David W. Allender, J. William Doane, M. Vilfan, I. Vilfan
Finite Molecular Anchoring In The Escaped-Radial Nematic Configuration: A 2-H-Nmr Study, G. P. Crawford, David W. Allender, J. William Doane, M. Vilfan, I. Vilfan
David W Allender
The director-field configuration of a nematic liquid crystal confined to cylindrical cavities of polycarbonate Nuclepore membranes ranging from 0.3 to 0.05-mu-m in radius is determined using deuterium nuclear magnetic resonance (H-2 NMR). Spectral patterns from cavities of radius 0.3-mu-m reveal the escaped-radial configuration with singular point defects, but as the cylinder size is decreased, the elastic energy imposed by the curvature of the confining walls competes with the anchoring energy to tilt the directors away from their preferred perpendicular anchoring direction, preventing the expected transition to the planar-radial configuration. A surface fitting parameter is directly determined by simulating H-2-NMR line …
Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Jr Dennison, Amberly Evans, Justin Dekany
Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Jr Dennison, Amberly Evans, Justin Dekany
Gregory Wilson
Measurements of the charge distribution in electron-bombarded, thin-film, multilayer dielectric samples showed that charging of multilayered materials evolves with time and is highly dependent on incident energy; this is driven by electron penetration depth, electron emission and material conductivity. Based on the net surface potential’s dependence on beam current, electron range, electron emission and conductivity, measurements of the surface potential, displacement current and beam energy allow the charge distribution to be inferred. To take these measurements, a thin-film disordered SiO2 structure with a conductive middle layer was charged using 200 eV and 5 keV electron beams with regular 15 s …
Approximation Of Range In Materials As A Function Of Incident Electron Energy, Gregory Wilson, Jr Dennison
Approximation Of Range In Materials As A Function Of Incident Electron Energy, Gregory Wilson, Jr Dennison
Gregory Wilson
A simple composite analytic expression has been developed to approximate the electron range in materials. The expression is applicable over more than six orders of magnitude in energy (<10 eV to >10 MeV) and range (10-9 m to 10-2 m), with uncertainty of ≤20% for most conducting, semiconducting and insulating materials. This is accomplished by fitting data from two standard NIST databases [ESTAR for the higher energy range and the electron IMFP (inelastic mean free path) for the lower energies]. In turn, these data have been fit with well-established semi-empirical models for range and IMFP that are related to standard materials properties …
Biaxiality In A Cyclic Thermotropic Nematic Liquid-Crystal, Jian-Feng Li, V. Percec, Ch. Rosenblatt, Oleg Lavrentovich
Biaxiality In A Cyclic Thermotropic Nematic Liquid-Crystal, Jian-Feng Li, V. Percec, Ch. Rosenblatt, Oleg Lavrentovich
Oleg Lavrentovich
Birefringence and textural data are presented for a ring-shaped trimeric liquid crystal. The material apparently undergoes a uniaxial-to-biaxial nematic phase transition as a function of temperature.