Scalar Perturbations in Scalar Field Quantum Cosmology

In this paper it is shown how to obtain the simplest equations for the Mukhanov-Sasaki variables describing quantum linear scalar perturbations in the case of scalar fields without potential term. This was done through the implementation of canonical transformations at the classical level, and unitary transformations at the quantum level, without ever using any classical background equation, and it completes the simplification initiated in investigations by Langlois \cite{langlois}, and Pinho and Pinto-Neto \cite{emanuel2} for this case. These equations were then used to calculate the spectrum index $n_s$ of quantum scalar perturbations of a non-singular inflationary quantum background model, which starts at infinity past from flat space-time with Planckian size spacelike hypersurfaces, and inflates due to a quantum cosmological effect, until it makes an analytical graceful exit from this inflationary epoch to a decelerated classical stiff matter expansion phase. The result is $n_s=3$, incompatible with observations.Comment: 10 pages, 2 figures, accepted version to Physical Review D 7

Evaluation of a computer-generated perspective tunnel display for flight path following

The display was evaluated by monitoring pilot performance in a fixed base simulator with the vehicle dynamics of a CH-47 tandem rotor helicopter. Superposition of the predicted future vehicle position on the tunnel image was also investigated to determine whether, and to what extent, it contributes to better system performance (the best predicted future vehicle position was sought). Three types of simulator experiments were conducted: following a desired trajectory in the presence of disturbances; entering the trajectory from a random position, outside the trajectory; detecting and correcting failures in automatic flight. The tunnel display with superimposed predictor/director symbols was shown to be a very successful combination, which outperformed the other two displays in all three experiments. A prediction time of 4 to 7 sec. was found to optimize trajectory tracking for the given vehicle dynamics and flight condition. Pilot acceptance of the tunnel plus predictor/director display was found to be favorable and the time the pilot needed for familiarization with the display was found to be relatively short

Do subleading corrections to Bekenstein-Hawking entropy hold the key to quantum gravity?

Black-holes are considered to be theoretical laboratories for testing models of quantum gravity. It is usually believed that any candidate for quantum gravity must explain the microscopic origin of the Bekenstein-Hawking ($S_{_{\rm BH}}$) entropy. In this letter, we argue (i) the requirement for a candidate approach to go beyond $S_{_{\rm BH}}$ and provide generic subleading corrections, and (ii) the importance to {\it disentangle} and identify the degrees of freedom leading to $S_{_{\rm BH}}$ and its subleading corrections. Using the approach of entanglement of modes across the horizon, we show that the microscopic degrees of freedom that lead to $S_{_{\rm BH}}$ and subleading corrections are different. We further show, using microcanonical and canonical ensemble approaches, that the quantum entanglement predicts generic power-law corrections to $S_{_{\rm BH}}$ and that the corrections can be identified with the kinematical properties of the event-horizon.Comment: 6 pages, Final version, To appear in MPL

Indexing Attentional Focus: A Critical Neural Element of Athletic Performance

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Announcement Effects on Bank Stock Prices: Citicorp\u27s Increase in Loan Loss Reserves For Third World Debt

Citicorp\u27s announcement of a sizeable increase to its loan loss reserve account was a landmark public admission of possible loan default by Third World debtor nations. This paper analyzes the impact of the announcement on Citicorp, the banking industry, and the stock market. The results provide evidence of a positive response to Citicorp\u27s action. There is additional evidence that the size of the market response is related to an individual bank\u27s degree of international loan exposure

Pre-operational baseline studies of selected nearshore marine biota at the Diablo Canyon power plant site: 1979-1982

This is the final report of the California Department of Fish and Games intertidal and subtidal surveys of plants and animals in the vicinity of the Diablo Canyon Power Plant. These studies cover the period from 1979 through 1982. Our previous report (Gotshall, et al. 1984) covered the period from 1973 through 1978. The report includes abundances and statistical analyses of comparisons of abundances between years and study areas for selected intertidal and subtidal plants and animals. A total of 556 random subtidal stations, 540 intertidal stations and 67 permanent abalone transects were completed during this report period. Trends in abundances of most species observed during our 1973 through 1978 studies continued, i.e. the population of giant red sea urchins remained at a very low level, bull kelp Nereocystis leutkeana densities continued to decline in Diablo Cove and North Control. These two trends are probably due to the effects of continued sea otter foraging in the study area. Our observations of the presence or absence of fishes at subtidal 30m stations indicate a continued decline in the abundances of lingcod, Ophiodon elongatus and a decline in the abundance of blue rockfish since the 1973 through 1978 study period. A new study was begun during this study period, the use of baited stations to obtain relative abundance indices for those species of fishes attracted to the bait. Black-and-yellow rockfish were the most frequently observed fishes at Diablo Cove stations, while blue rockfish were the most frequently observed fish at North control baited stations. (Document has 393 pages

The Significance of Porfolio Lenders to Real Estate Brokers

For the reasons observed in the sample of mortgage loans examined, the real estate brokerage industry will continue to depend heavily on portfolio lending to finance residential housing transactions. This paper examines a sample of residential mortgages to determine the breadth of lending by home type and customer credit qualification. The findings show that portfolio lending is required to satisfy homebuyers with heterogenous mortgage loan needs. Comparative analysis of credit decisions provides evidence of sound lending.

Invasive Grasses Consistently Create Similar Plant-soil Feedback Types in Soils Collected from Geographically Distant Locations

Aims Plants of similar life forms and closely related species have been observed to create similar types of plant–soil feedbacks (PSFs). However, investigations of the consistency of PSFs within species have not yielded clear results. For example, it has been reported that species create different types of PSFs in their native and introduced ranges. The aim of this project is to examine if four species create similar PSF types from soils collected from widely distributed areas within their introduced range. The soil for this project was collected from three areas in western North America. With this design, we aim to determine species- and site-specific ability to create PSFs and if the type of PSF created is consistent in all soil from all three collection areas. The species examined are Agropyron cristatum, Centaurea solstitialis, Poa pratensis and Taeniatherum caput-medusae. Methods We used three-field collected soils (from northern Nevada, western Montana and eastern Montana) in a two-phase greenhouse experiment to quantify the type of PSFs created by four invasive species. The first phase was a conditioning phase wherein each invasive species created species-specific changes to the soil. The second phase of the experiment was the response phase wherein both the conditioning species and a native phytometer were grown in the conditioned soil and in unconditioned (control) soil. The final aboveground biomass was used to evaluate the effect of conditioning and to determine the type of PSF created by each invasive species. Important Findings Our results suggest that three of our four study species did show consistency in relation to PSF. Two species A. cristatum and T. caputmedusae consistently created PSF types that benefit conspecifics more than heterospecifics (and thus are ‘invasive’ PSF types) and P. pratensis consistently exhibited no, or ‘neutral’, feedbacks. The fourth species (C. solstitialis) was inconsistent: in one soil, no feedback was created; in other soil, an invasive PSF was created and in the last soil, a feedback that relatively benefited the native phytometer was created. Thus, PSFs appear to uniformly contribute to the success of two species (A. cristatum and T. caput-medusae) but not C. solstitialis nor P. pratensis