Economics: The next physical science?

We review an emerging body of work by physicists addressing questions of economic organization and function. We suggest that, beyond simply employing models familiar from physics to economic observables, remarkable regularities in economic data may suggest parts of social order that can usefully be incorporated into, and in turn can broaden, the conceptual structure of physics.Comment: 9 pages, 6 figures, to appear in Physics Toda

Natural gauge mediation with a bino NLSP at the LHC

Natural models of supersymmetry with a gravitino LSP provide distinctive signatures at the LHC. For a neutralino NLSP, sparticles can decay to two high energy photons plus missing energy. We use the ATLAS diphoton search with 4.8 fb^{-1} of data to place limits in both the stop-gluino and neutralino-chargino mass planes for this scenario. If the neutralino is heavier than 50 GeV, the lightest stop must be heavier than 580 GeV, the gluino heavier than 1100 GeV and charginos must be heavier than approximately 300-470 GeV. This provides the first nontrivial constraints in natural gauge mediation models with a neutralino NLSP decaying to photons, and implies a fine tuning of at least a few percent in such models.Comment: 10 pages, 3 figures; v2: updated figure 3, version published in PR

Economics: the next physical science?

We review an emerging body of work by physicists addressing questions of economic organization and function. We suggest that, beyond simply employing models familiar from physics to economic observables, remarkable regularities in economic data may suggest parts of social order that can usefully be incorporated into, and in turn can broaden, the conceptual structure of physics.Economic theory, Physics, Econo-physics

Migration Patterns of Young Adults Reared in Jackson County, Tennessee

Most Tennessee counties have experienced a net outmigration of persons in recent decades. For example, net outmigration for Tennessee was over one-fourth of a million persons from 1950 to 1960 or half of the level of natural population increase during this period. During the 1950-60 decade, 86 of the 95 counties had a net outmigration of persons. In 59 counties outmigration was sufficient to result in an aggregate population decline. Counties experiencing greatest population declines are largely rural containing few urban centers. The questions of who leaves and who stays in low income rural areas and the effects of leaving or staying have often been the subject of debate. Resolution of these questions is of great importance for those directing policy in various sectors of our society. Nevertheless, relevant data pertaining to such questions are few. While net migration figures can be estimated from the Census and Vital Statistics, these sources provide few precise data for estimating the parameters of the migrating and nonmigrating sectors. To provide more precise information on migration relationships, an exploratory study was conducted in Jackson County, Tennessee. Jackson County, located in the Cumberland Plateau Area, is a low-income rural county and has experienced high outmigration for the past several decades. In the 1950-60 decade, net outmigration was 35 percent of the 1950 population and the third highest of any Tennessee county. The population of Jackson County declined from 12,348 in 1950 to 9,233 in 1960, a 25 percent decrease and the highest rate of decline of any Tennessee county in the 1950-60 decade. In 1960, 63 percent of the population was classified as rural farm while 44 percent of the civilian labor force was employed in agriculture. Only 10 percent of the civilian labor force in Tennessee and 6 percent of the United States labor were employed in agriculture. Seventeen percent of the Jackson County labor force was employed in manufacturing compared to 26 percent for Tennessee and 27 percent for the United States. Median family income in 1960 was the third lowest of any Tennessee county, and only 30 percent of the United States and 43 percent of the Tennessee averages. Jackson County was selected for study because it represented a low-income and high-outmigration area with limited local employment opportunity. Much of the land in Jackson County is not adapted to mechanized farming, therefore, agriculture, the major employer of the labor force, has not been particularly profitable. The roughness of most of the uplands restricts their use for crop production. Overall, less than one-fourth of the agricultural area is suitable for regular cultivation. Burley tobacco represents the principal cash crop on many farms although agriculture is based more on livestock than on crop production. A basic problem in the Upper Cumberland Plateau Area of Tennessee is the overabundance of human resources relative to local employment opportunities. Low-production farming areas such as represented by Jackson County often lack the necessary natural resources and adequately trained manpower to compete successfully in attracting nonfarm employment opportunities. Thus, large numbers of people have left such areas to seek better opportunities elsewhere. Evidence also indicates that many low-income rural communities receive a low return on their investment in educating children due to high outmigration. Each migrant represents a large public expenditure of local funds. Where there is a sizeable net loss of young adults, resources devoted to education and training of the young people are in the immediate sense lost to the community. Urban areas receiving these young people, oh the other hand, benefit from this nonreciprocal migration of new members of the labor force. Heaviest migration occurs among individuals in the younger age groups. This selective migration changes the composition of the community from which they migrated. There is a depletion of productive manpower and an increasing proportion of people in the dependent age groups. Rural communities experiencing high outmigration are less able to support their businesses, schools, churches, and other social organizations. The consequences of a population decline on rural communities are both positive and negative. Population losses may reduce the pressure on the available resources. On the other hand, it may also weaken the business community. The phenomenon of migration has been variously regarded as a means for achieving a more productive and balanced national economy and as a way of raising the level of living. It also has been regarded as a drain on the talent and economic resources of agricultural areas, and as producing a weakened national character. With these problems in mind, the primary in mind, the primary objective of the present study are: (1) to determine the extent and pattern of migration of young adults reared in Jackson County, and (2) to relate these migration patterns to educate, occupation, residence, special job training, and level of living

The potential role of livestock in a nuclear-powered agro-industrial complex in the United Arab Republic

The general objective of this study was to evaluate the potential role of livestock in an agricultural-industrial complex in the Middle East, and specifically for a potential site west of Alexandria in the United Arab Republic. Several analytical models were developed to determine the optimum organization of crop and livestock activities in terms of six alternative goals. These were: (1) maximizing financial returns, (2) maximizing the present value of foreign exchange net credit, (3) maximizing calorie production, (4) maximizing effective protein production, (5) maximizing domestic employment, and (6) minimizing investment capital required for the agricultural complex. Important sources of published data used in synthesizing live stock production coefficients were the various publications of the state agricultural experiment stations and extension services in the United States, publications of the United States Department of Agriculture and releases prepared by the Food and Agriculture Organization of the United Nations. Data relating to basic resources and investments in the agroindustrial complex were developed by other members of the Middle East Study Group. Data pertaining to crops were synthesized by members of the agricultural sector of the study team. The annual Income which was provided by various systems selected in each optimization model varied considerably. Relatively high levels of income were provided in the income, foreign exchange, and employment models, while income levels were much lower in the nutrition and investment models. The net return value, excluding water cost, in the income model was $27.8 million, as compared to only$5.6 million in the calorie model. Employment which would be provided was also considerably higher in the income, foreign exchange, and employment models than in the nutrition and investment models. The man-hours of employment to be provided totaled 11.4 million man-hours in the employment model but only 2.8 million man-hours in the calorie model. The quantity of calories and protein provided varied to a lesser extent among the models than did other alternative goal characteristics. The maximum quantity of calories, amounting to 1236 billion, was provided in the calorie model. The quantity of calories provided by the income model, on the other hand, was 556 billion. The maximum quantity of protein was provided by the protein model (50 million pounds). This compares with 34 million pounds of protein which were produced in the income model. Livestock production was included in four of the six optimum systems developed by the various models. Although the greatest contribution of livestock was in terms of income and foreign exchange, contributions to the nutrition and employment goals were quite significant in some models. In order to evaluate the sensitivity of net returns to the water desalination cost, the cost of water was deducted from the estimated income for each of the various optimization models at cost levels rang ing from $.10 to$.45 per thousand gallons. Break-even prices for water were also calculated. Of the 13 sale crops analyzed, only five could break even with water production cost at $.20 per thousand gallons. Only two crops showed a break-even water price of as much as$.35 per thousand gallons, which is considered to be the most likely for about 1980. The break-even water prices for the crop and livestock production systems selected in the six optimization models varied from $.09 per thousand gallons in the maximum calorie model to$.47 per thousand gallons in the maximum income model, The calorie model included no livestock in the production system, while the income model included livestock activities at the upper allowable levels

Conceptual design of a synchronous Mars telecommunications satellite

Future missions to Mars will require a communications system to link activities on the Martian surface with each other and with mission controllers on Earth. A conceptual design is presented for an aerosynchronous communications satellite to provide these links. The satellite provides the capability for voice, data/command, and video transmissions. The mission scenario assumed for the design is described, and a description of a single aerosynchronous satellite is explained. A viable spacecraft design is then presented. Communication band selection and channel allocation are discussed. The communications system conceptual design is presented along with the trades used in sizing each of the required antennas. Also, the analyses used to develop the supporting subsystem designs are described as is the communications impact on each subsystem design

Autocorrelation of ratios of L-functions

We give a new heuristic for all of the main terms in the quotient of products of L-functions averaged over a family. These conjectures generalize the recent conjectures for mean values of L-functions. Comparison is made to the analogous quantities for the characteristic polynomials of matrices averaged over a classical compact group.Comment: Minor correction

Wave Kinematics at High Sea States

Measurements of currents close to the ocean surface and within the crests of large, steep waves have been acquired with an incoherent bistatic sonar mounted on the seafloor. The sonar uses a single narrow-beam transmitter/receiver and three fan-beam receivers set in a triangular configuration around the source. Acoustic pulses transmitted from the seafloor are scattered by bubble clouds and the sea surface to the four receivers and may be transformed into velocity components as a function of elevation. Individual estimates of the currents at, and close to, the surface are made with sufficient temporal resolution to identify kinematics in the crests of large waves. Observations acquired in the Danish sector of the North Sea are examined to evaluate both the potential merits and limitations of the measurement approach. At lower wind speeds, sidelobe scatter from the surface reaches the receiver simultaneously with the volume scattered signal arriving from a few meters beneath, contaminating the velocity measurement at this depth. At higher wind speeds, bubble clouds and increased roughness of the surface combine to suppress this effect, permitting reliable near-surface measurement. A numerical simulation has been implemented to explore some aspects of sonar performance including turbulent velocity fluctuations and bubble density gradients. Additional analysis is carried out to examine bubble suppression of sidelobe scatter. The observations lead to some conclusions regarding wave kinematics during a storm in which the wind speed reached ∼17 m s−1. At the ocean surface, the downwind velocity in the crests of large waves substantially exceeds that predicted by the second-order Stokes model, but in the wave troughs the current is close to the nonlinear prediction

Should we still believe in constrained supersymmetry?

We calculate Bayes factors to quantify how the feasibility of the constrained minimal supersymmetric standard model (CMSSM) has changed in the light of a series of observations. This is done in the Bayesian spirit where probability reflects a degree of belief in a proposition and Bayes' theorem tells us how to update it after acquiring new information. Our experimental baseline is the approximate knowledge that was available before LEP, and our comparison model is the Standard Model with a simple dark matter candidate. To quantify the amount by which experiments have altered our relative belief in the CMSSM since the baseline data we compute the Bayes factors that arise from learning in sequence the LEP Higgs constraints, the XENON100 dark matter constraints, the 2011 LHC supersymmetry search results, and the early 2012 LHC Higgs search results. We find that LEP and the LHC strongly shatter our trust in the CMSSM (with $M_0$ and $M_{1/2}$ below 2 TeV), reducing its posterior odds by a factor of approximately two orders of magnitude. This reduction is largely due to substantial Occam factors induced by the LEP and LHC Higgs searches.Comment: 38 pages, 14 figures; version as published in EPJ