Ground state energy of spin-1/2 fermions in the unitary limit

We present lattice results for the ground state energy of a spin-1/2 fermion system in the unitary limit, where the effective range of the interaction is zero and the scattering length is infinite. We compute the ground state energy for a system of 6, 10, 14, 18, and 22 particles, with equal numbers of up and down spins in a periodic cube. We estimate that in the limit of large number of particles, the ground state energy is 0.25(3) times the ground state energy of the free Fermi system.Comment: 17 pages, 9 figures, expanded manuscript includes more data and cross-check

The Problem with Structural Unemployment in the U.S.

Following the most recent recession, an attempt has been made to explain current levels of unemployment as resulting from structural unemployment, or a mismatch between the skills of the unemployed and the types of jobs available. The evidence, however, indicates that the issue is actually a lack of aggregate demand. Since accepting one of these views over the other will lead to very different policy solutions, it is important to accurately assess the cause of unemployment.This issue brief finds that the evidence is overwhelming consistent with the view that a lack of demand, caused by the collapse of the housing bubble is at the root of U.S. unemployment. In this context, measures that focus on improving skills - a remedy for structural unemployment - will have little effect on overall employment

CBO Projects More Severe Downturn

The new economic projections from the Congressional Budget Office show the economy remaining well below its potential level of output until 2014. The projections show the unemployment rate averaging 10.2 percent in 2010 and gradually edging down to the long-term sustainable rate of 4.8 percent by 2014. Over this 4 year period, the workforce will face a substantially higher risk of unemployment or underemployment due to insufficient demand in the economy. This paper highlights some of the main implications of CBO's new economic projections

Increasing Inequality in the United States

This report traces the increase in U.S. inequality over the last quarter-century. It outlines the myriad drivers of this trend, including deliberate policy decisions on trade, immigration, interest rates, and health care costs. The paper was published and distributed in Germany through the Friedrich Ebert Foundation (IB200611A)

Invasive alien species : a threat to sustainable livelihoods in the Pacific? : an assessment of the effects of Wasmannia auropunctata (little fire ant) and Achatina fulica (giant African snail) on rural livelihoods in the Solomon Islands : a dissertation presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Development Studies, Massey University, Manawatū, New Zealand

Invasive alien species (IAS) are a global phenomenon and are recognised as a driver of environmental change which can affect the well-being of people in a multitude of ways. Despite this, the role of IAS in local livelihoods has received relatively little attention. Influencing all three of the sustainable development pillars (social, economic, environmental), IAS should be recognised as a significant development issue. But they are not. As such, IAS issues are new to many sectors and governments and therefore largely go unseen and un-actioned. Contemporary rural livelihoods in the Solomon Islands are heavily reliant on subsistence/semi-subsistence agriculture. Following a livelihoods’ framework developed for the Solomon Islands, this thesis explores the influence IAS have on rural livelihoods in this country. Using two qualitative case studies, Wasmannia auropunctata (little fire ant) and Achatina fulica (giant African snail), this study investigates how vulnerable/resilient rural livelihoods are to the effects of IAS and the implications IAS have for sustainable development in the Solomon Islands. The effects of IAS on rural livelihoods are complex and at times contradictory. W. auropunctata for the most part is not negatively affecting the dominant livelihood strategy (subsistence/semi-subsistence agriculture) practised in the Solomon Islands. While there are some social impacts associated with W. auropunctata, overall Solomon Island households can be considered resilient to this IAS. Achatina fulica is a different story. This species is negatively affecting the subsistence/semi-subsistence agricultural sector on which so many rural Solomon Island households depend. This has resulted in households implementing negative livelihood diversification measures as they fail to cope or adapt to the snails’ presence. Unlike for W. auropunctata, Solomon Island households have not demonstrated any resilience to A. fulica. Understanding how rural livelihoods are affected by various stressors and adverse events can help to design development policies and interventions geared towards building better lives for all people. This can only occur however, if the full range of shocks are recognised. To date, this is not the case for IAS, and as such, they are still a significant missing component of development policy