The Performance of Compliance Measures and Instruments for Nitrate Nonpoint Pollution Control Under Uncertainty and Alternative Agricultural Commodity Policy Regimes

Following Weitzman (1974), there is ample theoretical literature indicating that choice of pollution control instruments under conditions of uncertainty will affect the expected net benefits that can be realized from environmental protection. However, there is little empirical research on the ex ante efficiency of alternative instruments for controlling water, or other types of pollution, under uncertainty about costs and benefits. Using a simulation model that incorporates various sources of uncertainty, the ex ante efficiency of price and quantity controls applied to two alternative policy targets, fertilizer application rates and estimated excess nitrogen applications, are examined under varying assumptions about agricultural income support policies. Results indicate price instruments outperform quantity instruments. A tax on excess nitrogen substantially outperforms a fertilizer tax in the scenario with support programs, while the ranking is reversed in the scenario without support programs.Environmental Economics and Policy,

UNCERTAINTY AND THE REGULATION OF NITRATE POLLUTION FROM AGRICULTURE

A simulation of U.S. corn production compares four environmental policies for controlling agricultural nitrate pollution. Public uncertainty about key economic parameters are considered. Results indicate that policy choice is sensitive to commodity programs and the public information structure. Agricultural research benefits are also sensitive to agricultural environmental policy choices.environmental policy, nonpoint pollution, uncertainty, value of information, Environmental Economics and Policy,

Applying black hole perturbation theory to numerically generated spacetimes

Nonspherical perturbation theory has been necessary to understand the meaning of radiation in spacetimes generated through fully nonlinear numerical relativity. Recently, perturbation techniques have been found to be successful for the time evolution of initial data found by nonlinear methods. Anticipating that such an approach will prove useful in a variety of problems, we give here both the practical steps, and a discussion of the underlying theory, for taking numerically generated data on an initial hypersurface as initial value data and extracting data that can be considered to be nonspherical perturbations.Comment: 14 pages, revtex3.0, 5 figure

Cauchy-perturbative matching and outer boundary conditions I: Methods and tests

We present a new method of extracting gravitational radiation from three-dimensional numerical relativity codes and providing outer boundary conditions. Our approach matches the solution of a Cauchy evolution of Einstein's equations to a set of one-dimensional linear wave equations on a curved background. We illustrate the mathematical properties of our approach and discuss a numerical module we have constructed for this purpose. This module implements the perturbative matching approach in connection with a generic three-dimensional numerical relativity simulation. Tests of its accuracy and second-order convergence are presented with analytic linear wave data.Comment: 13 pages, 6 figures, RevTe

Cauchy-perturbative matching and outer boundary conditions: computational studies

We present results from a new technique which allows extraction of gravitational radiation information from a generic three-dimensional numerical relativity code and provides stable outer boundary conditions. In our approach we match the solution of a Cauchy evolution of the nonlinear Einstein field equations to a set of one-dimensional linear equations obtained through perturbation techniques over a curved background. We discuss the validity of this approach in the case of linear and mildly nonlinear gravitational waves and show how a numerical module developed for this purpose is able to provide an accurate and numerically convergent description of the gravitational wave propagation and a stable numerical evolution.Comment: 20 pages, RevTe

Toward an anisotropic atom-atom model for the crystalline phases of the molecular S8 compound

We analize two anisotropic atom-atom models used to describe the crystalline alpha,beta and gamma phases of S8 crystals, the most stable compound of elemental sulfur in solid phases, at ambient pressure and T<=400 K. The calculations are performed via a series of classical molecular dynamics (MD) simulations, with flexible molecular models and using a constant pressure-constant temperature algorithm for the numerical simulations. All intramolecular modes that mix with lattice modes, and are therefore relevant on the onset of structural phase transitions, are taken into account. Comparisons with experimental data and previous results obtained with an isotropic atom-atom molecular model are also performed.Comment: Major changes, new simulations and figures added, revtex4, to appear in J. Chem. Phy

The collision of boosted black holes

We study the radiation from a collision of black holes with equal and opposite linear momenta. Results are presented from a full numerical relativity treatment and are compared with the results from a ``close-slow'' approximation. The agreement is remarkable, and suggests several insights about the generation of gravitational radiation in black hole collisions.Comment: 8 pages, RevTeX, 3 figures included with eps

The Emergence of Critical Social Theory in American Jurisprudence: An Introduction to Professor Rosenberg\u27s Perspective

Norman Rosenberg\u27s treatment of Thomas Cooley, liberal jurisprudence, and the law of libel exemplifies both a difficulty with and an opportunity for traditional law review scholarship. The difficulty arises from the failure of many legal writers to identify and explain the jurisprudential perspectives that define their substantive approach. This problem is particularly acute when, as in Professor Rosenberg\u27s article, the jurisprudential perspective deviates from the mainstream. The opportunity lies in bringing the problem of perspective out of the closet and legitimating its critical treatment as an integral element of all legal scholarship

Comment on "Zeeman-Driven Lifshitz Transition: A Model for the Experimentally Observed Fermi-Surface Reconstruction in YbRh2Si2"

In Phys. Rev. Lett. 106, 137002 (2011), A. Hackl and M. Vojta have proposed to explain the quantum critical behavior of YbRh2Si2 in terms of a Zeeman-induced Lifshitz transition of an electronic band whose width is about 6 orders of magnitude smaller than that of conventional metals. Here, we note that the ultra-narrowness of the proposed band, as well as the proposed scenario per se, lead to properties which are qualitatively inconsistent with the salient features observed in YbRh2Si2 near its quantum critical point.Comment: 3 page