Gravitational Dynamics From Entanglement "Thermodynamics"

In a general conformal field theory, perturbations to the vacuum state obey the relation \delta S = \delta E, where \delta S is the change in entanglement entropy of an arbitrary ball-shaped region, and \delta E is the change in "hyperbolic" energy of this region. In this note, we show that for holographic conformal field theories, this relation, together with the holographic connection between entanglement entropies and areas of extremal surfaces and the standard connection between the field theory stress tensor and the boundary behavior of the metric, implies that geometry dual to the perturbed state satisfies Einstein's equations expanded to linear order about pure AdS.Comment: v2: references added, problematic section on Radon transform remove

Cognitive Sensor Platform

This paper describes a platform that is used to build embedded sensor systems for low energy implantable applications. One of the key characteristics of the platform is the ability to reason about the environment and dynamically modify the operational parameters of the system. Additionally the platform provides to ability to compose application specific sensor systems using a novel computational element that directly supports a synchronous-dataflow (SDF) programming paradigm. Cognition in the context of a sensor platform is defined as the “process of knowing, including aspects of awareness, perception, reasoning, and judgment”.DOI:http://dx.doi.org/10.11591/ijece.v4i4.568

AGRICULTURAL COOPERATIVES AND RISK MANAGEMENT:IMPACT ON FINANCIAL PERFORMANCE

Agricultural cooperatives, like all agribusinesses, operate in an inherently risky environment. Many risk management tools exist, but agricultural cooperatives have been slow to adopt sophisticated risk management practices. Using simulation methods, this paper presents insight into how both traditional and innovative risk management practices effect the distribution of key financial variables for agricultural cooperatives.Agribusiness,

RISK MANAGEMENT TECHNIQUES FOR AGRICULTURAL COOPERATIVES: AN EMPIRICAL EVALUATION

While not ignoring risk, agricultural cooperatives tend to accommodate risk through the holding of internal capital reserves rather than engage in active risk management. A lack of information regarding the risk, returns, and the effect on cooperative financial performance of both traditional and innovative risk management strategies is likely a constraint to the adoption of active risk management by cooperatives. In this research, we examine the influence of alternative risk management strategies on cooperative financial performance, namely the return on assets (ROA) of grain merchandising cooperatives of various sizes. Strategies include traditional exchange traded futures and options strategies, an over-the-counter revenue swap, throughput insurance, and combinations of price and throughput strategies. Each of these strategies, for small, medium, and large size firms, are evaluated using a range of procedures including techniques which rely on mean-variance efficiency as well as evaluation procedures which help determine the ability of a strategy to mitigate downside risk. The results of the simulation exercise provide considerable support for the routine buying of at-the-money put options in setting a commodity floor price. The results also support the use, and perhaps the development, of insurance on cooperative throughput if the insurance product is used in conjunction with a price risk management strategy, in essence providing a hedge against downfalls in revenue. Over-the-counter revenue swaps, while intuitively appealing, did not perform well on average relative to more traditional exchange traded products. This result is especially important given the added counter party risk associated with such contracts. However, in some cases, the revenue swap, as well routine hedging with futures, performed better under a Value-at-Risk evaluation criteria than with a mean-variance criteria. Hence, it is important for cooperative managers to consider these results in the context of the risk management goals.Agribusiness,

Merger arbitrage in Germany

This paper analyses the risk and return characteristics from a merger arbitrage trading strategy in Germany for the first time. The extant literature focuses mainly on data sets from Anglo-American based jurisdictions with mixed results. We argue that because in Germany i) acquisition laws bias consideration toward cash bids thereby decreasing the uncertainty of announced transactions (versus share offers) and ii) the Aufsichstrat (supervisory board with employee participation) has corporate governance oversight over any proposed merger such that only bids tacitly approved by it are likely to be announced in the first instance, a merger arbitrage trading strategy in a German setting will have different risk and return characteristics. To estimate the significance of merger arbitrage returns we construct a realistic measure of risk arbitrage which factors in transaction costs and other practical limitations encountered by arbitrageurs employing this strategy. We also construct two additional portfolios, an equally-weighted portfolio and a value weighted portfolio, for comparison purposes. The results show that the practical risk arbitrage manager portfolio fails to outperform on a risk-adjusted basis indicating that insofar as the German setting yields benefits in the form of lower risk, these are properly priced by the market

Survival of fossils under extreme shocks induced by hypervelocity impacts

Experimental data are shown for survival of fossilized diatoms undergoing shocks in the GPa range. The results were obtained from hypervelocity impact experiments which fired fossilized diatoms frozen in ice into water targets. After the shots, the material recovered from the target water was inspected for diatom fossils. Nine shots were carried out, at speeds from 0.388 to 5.34?km?s?1, corresponding to mean peak pressures of 0.2–19?GPa. In all cases, fragmented fossilized diatoms were recovered, but both the mean and the maximum fragment size decreased with increasing impact speed and hence peak pressure. Examples of intact diatoms were found after the impacts, even in some of the higher speed shots, but their frequency and size decreased significantly at the higher speeds. This is the first demonstration that fossils can survive and be transferred from projectile to target in hypervelocity impacts, implying that it is possible that, as suggested by other authors, terrestrial rocks ejected from the Earth by giant impacts from space, and which then strike the Moon, may successfully transfer terrestrial fossils to the Moon

The Multidimensional Mortality Awareness Measure & Model (MMAMM): Development and validation of a new self-report questionnaire & psychological framework

For each of eight literature-identified conceptual dimensions of mortality awareness, questionnaire items were generated, producing 89 in all. 359 participants responded to these items and to questionnaires measuring health attitudes, risk-taking, rebelliousness and demographic variables. Multivariate correlational analyses investigated the underlying structure of the item pool and the construct validity as well as the reliability of the emergent empirically derived subscales. Five components, rather than eight, were identified. Given the item content of each, the associated mortality awareness subscales were labelled as: legacy, fearfulness, acceptance, disempowerment, and disengagement. Each attained an acceptable level of internal reliability. Relationships with other variables supported the construct validity of these empirically derived subscales and more generally of this five-factor model. In conclusion, this new multidimensional measure and model of mortality awareness extends our understanding of this important aspect of human existence and supports a more integrative and optimistic approach to mortality awareness than previously available