The Benefits of Campaign Spending

Critics of American politics often say that spending on electoral campaigns harms our democracy. They charge that the money goes for cynical, negative, and misleading advertisements that alienate the public from politics and elections. Political scientists have collected and analyzed data on the connection between campaign spending and civic life. The data bear on several questions at issue in campaign finance debates: Does campaign spending reduce public trust? Does it reduce levels of citizen involvement in or attention to campaigns? Does it lower citizens' knowledge of information relevant to their votes? Who benefits from campaign spending? Studies indicate that campaign spending does not diminish trust, efficacy, and involvement, contrary to what critics charge. Moreover, spending increases public knowledge of the candidates, across essentially all groups in the population. Less spending on campaigns is not likely to increase public trust, involvement, or attention. Implicit or explicit spending limits reduce public knowledge during campaigns. Getting more money into campaigns should, on the whole, be beneficial to American democracy

Transport anomalies in a simplified model for a heavy electron quantum critical point

We discuss the transport anomalies associated with the development of heavy electrons out of a neutral spin fluid using the large-N treatment of the Kondo-Heisenberg lattice model. At the phase transition in this model the spin excitations suddenly acquire charge. The Higgs process by which this takes place causes the constraint gauge field to loosely ``lock'' together with the external, electromagnetic gauge field. From this perspective, the heavy fermion phase is a Meissner phase in which the field representing the difference between the electromagnetic and constraint gauge field, is excluded from the material. We show that at the transition into the heavy fermion phase, both the linear and the Hall conductivity jump together. However, the Drude weight of the heavy electron fluid does not jump at the quantum critical point, but instead grows linearly with the distance from the quantum critical point, forming a kind of ``gossamer'' Fermi-liquid.Comment: 15 pages, 3 figures. Small change in references in v

Using template/hotwire cutting to demonstrate moldless composite fabrication

The objective of this experiment is to provide a simple, inexpensive composite fabrication technique which can be easily performed with a minimum of equipment and facilities. This process eliminates expensive female molds and uses only male molds which are easily formed from foam blocks. Once the mold is shaped, it is covered with fiberglass and becomes a structural component of the product

Quadratic diffusion Monte Carlo and pure estimators for atoms

The implementation and reliability of a quadratic diffusion Monte Carlo method for the study of ground-state properties of atoms are discussed. We show in the simple yet non-trivial calculation of the binding energy of the Li atom that the method presented is effectively second-order in the time step. The fulfilment of the expected quadratic behavior relies on some basic requirements of the trial wave function used for importance sampling, in the context of the fixed-node approximation. Expectation values of radial operators are calculated by means of a pure estimation based on the forward walking methodology. It is shown that accurate results without extrapolation errors can be obtained with a pure algorithm that can be easily implemented in any previous diffusion Monte Carlo program.Comment: RevTex, 20 pages, 3 figures, accepted in J. Chem. Phy

Source Reconstruction as an Inverse Problem

Inverse Problem techniques offer powerful tools which deal naturally with marginal data and asymmetric or strongly smoothing kernels, in cases where parameter-fitting methods may be used only with some caution. Although they are typically subject to some bias, they can invert data without requiring one to assume a particular model for the source. The Backus-Gilbert method in particular concentrates on the tradeoff between resolution and stability, and allows one to select an optimal compromise between them. We use these tools to analyse the problem of reconstructing features of the source star in a microlensing event, show that it should be possible to obtain useful information about the star with reasonably obtainable data, and note that the quality of the reconstruction is more sensitive to the number of data points than to the quality of individual ones.Comment: 8 pages, 3 figures. To be published in "Microlensing 2000, A New Era of Microlensing Astrophysics", eds., J.W. Menzies and P.D. Sackett, ASP Conference Serie

A Characterisation of the Weylian Structure of Space-Time by Means of Low Velocity Tests

The compatibility axiom in Ehlers, Pirani and Schild's (EPS) constructive axiomatics of the space-time geometry that uses light rays and freely falling particles with high velocity, is replaced by several constructions with low velocity particles only. For that purpose we describe in a space-time with a conformal structure and an arbitrary path structure the radial acceleration, a Coriolis acceleration and the zig-zag construction. Each of these quantities give effects whose requirement to vanish can be taken as alternative version of the compatibility axiom of EPS. The procedural advantage lies in the fact, that one can make null-experiments and that one only needs low velocity particles to test the compatibility axiom. We show in addition that Perlick's standard clock can exist in a Weyl space only.Comment: to appear in Gen.Rel.Gra