Is China’s Growth Sustainable?

A central pillar of the sustainability movement is the call to include environmental accounting in standard measures of economic performance. This increased transparency would, in principle, mitigate the temptation of economic managers and policy makers to increase growth in material consumption at the expense of the environment. Moreover, as Repetto (1989) and others have argued, deducting depreciation of produced capital from NNP but not deducting depreciation of natural capital is inconsistent and debases NNP as a possible indicator of welfare. Based on the evidence available, it appears that while GNNP is substantially less than NNP, these adjustments do not adversely compromise existing estimates of economic growth for China.sustainable development, China, genuine saving, SOx, NOx, TSP, resource depletion, natural capital, Environmental Kuznets Curve, green net national product

Delaying the Catastrophic Arrival of the Brown Tree Snake to Hawaii

This paper develops a two-stage model for the optimal management of a potential invasive species. The arrival of an invasive species is modeled as an irreversible event with an uncertain arrival time. The model is solved in two stages, beginning with the post-invasion stage. In this stage, we assume perfect certainty regarding population size and arrivals. The loss-minimizing paths of prevention and control are identified, resulting in a minimized present value penalty associated with the invasion. After calculating this penalty, we analyze the pre-invasion stage and solve for the level of prevention expenditures that will minimize expected total cost. For the case of the Brown Tree Snake potentially invading Hawaii, we find that under a regime of precommitment, pre-invasion expenditures on prevention should be approximately $3.2 million today, decreasing every year until invasion. However, if the planner is permitted to re-evaluate the threat following a non-event, prevention will be lower ($2.96 million a year) and constant until invasion. Once invasion occurs, optimal management requires lower annual expenditures on prevention ($3.1 million) but requires$1.6 million to be spent on control annually to keep the population at its steady state level.catastrophe, hazard function, invasive species, Brown Tree Snake, Boiga irregularis, prevention and control, Hawaii

Control of Invasive Species: Lessons from Miconia in Hawaii

Once established, invasive species can rapidly and irreversibly alter ecosystems and degrade the value of ecosystem services. Optimal control of an exotic pest solves for a trajectory of removals that minimizes the present value of removal costs and residual damages from the remaining pest population. The shrubby tree, Miconia calvescens, is used to illustrate dynamic policy options for a forest invader. Potential damages to Hawaii's forest ecosystems are related to decreased aquifer recharge, biodiversity, and other ecosystem values. We find that population reduction is the optimal management policy for the islands of Oahu, Maui, and Hawaii. On the island of Kauai, where tree density is lower and search costs higher, optimal policy calls for deferring removal expenditures until the steady state population is reached.

Environmental Policy Issues for Sustainable Economic Development in China

A central pillar of the sustainability movement is the call to include environmental accounting in standard measures of economic performance. This increased transparency would, in principle, mitigate the temptation of economic managers and policy makers to increase growth in material consumption at the expense of the environment. Moreover, as Repetto (1989) and others have argued, deducting depreciation of produced capital from NNP but not deducting depreciation of natural capital is inconsistent and debases NNP as a possible indicator of welfare. Based on the evidence available, it appears that while GNNP is substantially less than NNP, these adjustments do not adversely compromise existing estimates of economic growth for China.Environmental Economics and Policy,

Quantum imaging of spin states in optical lattices

We investigate imaging of the spatial spin distribution of atoms in optical lattices using non-resonant light scattering. We demonstrate how scattering spatially correlated light from the atoms can result in spin state images with enhanced spatial resolution. Furthermore, we show how using spatially correlated light can lead to direct measurement of the spatial correlations of the atomic spin distribution

Resource management for Sustainable Development of Island Economies

What is the role of resource management in sustaining competitiveness for island economies such as the Republic of the Philippines and Hawaii? We review the history of thought on sustainable resource management and sustainable development and then turn to the threats to sustainability from the resource curse and the parallel curse of paradise. We show how the resource curse undermines the pursuit of sustainability and describe innovations in governance that can transform the curse into a blessing.Resource curse, sustainable development, Dutch disease

Modeling the electron with Cosserat elasticity

We suggest an alternative mathematical model for the electron in dimension 1+2. We think of our (1+2)-dimensional spacetime as an elastic continuum whose material points can experience no displacements, only rotations. This framework is a special case of the Cosserat theory of elasticity. Rotations of material points are described mathematically by attaching to each geometric point an orthonormal basis which gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory we choose a coframe and a density. We then add an extra (third) spatial dimension, extend our coframe and density into dimension 1+3, choose a conformally invariant Lagrangian proportional to axial torsion squared, roll up the extra dimension into a circle so as to incorporate mass and return to our original (1+2)-dimensional spacetime by separating out the extra coordinate. The main result of our paper is the theorem stating that our model is equivalent to the Dirac equation in dimension 1+2. In the process of analyzing our model we also establish an abstract result, identifying a class of nonlinear second order partial differential equations which reduce to pairs of linear first order equations