Temporary Programs to Extend Unemployment Compensation

[From Summary] The federal/state unemployment compensation (UC) system is designed to provide temporary and partial wage replacement to workers who have become involuntarily unemployed. UC also helps to stabilize the economy by providing unemployed workers with additional purchasing power, which serves as an economic stimulus when unemployment rises during recessions. The UC system generally provides sufficient duration of benefits during periods of economic prosperity, as most UC beneficiaries experience fewer weeks of unemployment than their maximum entitlements and return to work before their benefit rights are exhausted. However, during periods of economic decline, people tend to remain unemployed longer because of the greater difficulty in finding new jobs, and a rising proportion of jobless workers exhaust UC benefits without finding new work. Thus, programs have been established to increase the number of weeks of assistance during periods of high unemployment

Sudden future singularities in FLRW cosmologies

The standard energy conditions of classical general relativity are applied to FLRW cosmologies containing sudden future singularities. Here we show, in a model independent way, that although such cosmologies can satisfy the null, weak and strong energy conditions, they always fail to satisfy the dominant energy condition. They require a divergent spacelike energy flux in all but the comoving frame.Comment: revtex4. Added references and a definition. To appear in CQ

Galactic Potentials

The information contained in galactic rotation curves is examined under a minimal set of assumptions. If emission occurs from stable circular geodesic orbits of a static spherically symmetric field, with information propagated to us along null geodesics, observed rotation curves determine galactic potentials without specific reference to any metric theory of gravity. Given the potential, the gravitational mass can be obtained by way of an anisotropy function of this field. The gravitational mass and anisotropy function can be solved for simultaneously in a Newtonian limit without specifying any specific source. This procedure, based on a minimal set of assumptions, puts very strong constraints on any model of the "dark matter".Comment: A somewhat longer form of the final version to appear in Physical Review Letters.Clarification and further reference

Enhancing the thermal performance of temporary fabric structures for the advanced energy efficient shelter system

The focus of this research is to characterize the thermal load on temporary fabric shelters deployed in the Middle East in order to establish realistic contract specification for the thermal performance of future shelters. Three different testing methods were utilized to evaluate shelter thermal performance. Small-scale tests allowed for economical comparisons of different shelter materials and configurations

Optomechanically induced transparency and cooling in thermally stable diamond microcavities

Diamond cavity optomechanical devices hold great promise for quantum technology based on coherent coupling between photons, phonons and spins. These devices benefit from the exceptional physical properties of diamond, including its low mechanical dissipation and optical absorption. However the nanoscale dimensions and mechanical isolation of these devices can make them susceptible to thermo-optic instability when operating at the high intracavity field strengths needed to realize coherent photon--phonon coupling. In this work, we overcome these effects through engineering of the device geometry, enabling operation with large photon numbers in a previously thermally unstable regime of red-detuning. We demonstrate optomechanically induced transparency with cooperativity > 1 and normal mode cooling from 300 K to 60 K, and predict that these device will enable coherent optomechanical manipulation of diamond spin systems

Detection of zeptojoule microwave pulses using electrothermal feedback in proximity-induced Josephson junctions

We experimentally investigate and utilize electrothermal feedback in a microwave nanobolometer based on a normal-metal (\mbox{Au}_{x}\mbox{Pd}_{1-x}) nanowire with proximity-induced superconductivity. The feedback couples the temperature and the electrical degrees of freedom in the nanowire, which both absorbs the incoming microwave radiation, and transduces the temperature change into a radio-frequency electrical signal. We tune the feedback in situ and access both positive and negative feedback regimes with rich nonlinear dynamics. In particular, strong positive feedback leads to the emergence of two metastable electron temperature states in the millikelvin range. We use these states for efficient threshold detection of coherent 8.4 GHz microwave pulses containing approximately 200 photons on average, corresponding to 1.1 \mbox{ zJ} \approx 7.0 \mbox{ meV} of energy