The cutoff-dependence of the Casimir force within an inhomogeneous medium

We consider the ground state energy of the electromagnetic field in a piston geometry. In the idealised case, where the piston and the walls of the chamber are taken as perfect mirrors, the Casimir pressure on the piston is finite and independent of the small scale physics of the media that compose the mirrors; the Casimir-energy of the system can be regularised and is cutoff-independent. Yet we find that, when the body of the piston is filled with an inhomogeneous dielectric medium, the Casimir energy is cutoff-dependent, and the value of the pressure is thus inextricably dependent on the detailed behaviour of the mirror and the medium at large wave-vectors. This result is inconsistent with recent proposals for regularising Casimir forces in inhomogeneous media.Comment: 6 pages, 2 figure

Trace Metal Pollution in Narragansett Bay: A Case Study of the Rhode Island Quahog Fishery

This paper was written with two objectives in mind: to provide information relevant to the protection of the quahog fishery and the protection of human health. Both are threatened as hundreds of millions of gallons of industrial effluents and sewage treatment plant discharges enter Narragansett Bay daily. The implications of trace metal pollution with respect to the quahog fishery have received little attention to date. The purpose of this paper is to assemble scientific, legal, and socioeconomic information in a fashion which will direct future research and management attempts in an effective manner

Vacuum polarisation and the muon g-2 in lattice QCD

We measure the hadronic contribution to the vacuum polarisation tensor, and use it to estimate the hadronic contribution to (g-2)_mu, the muon anomalous magnetic moment.Comment: 3 pages, 4 figures, Latex. Talk given by P.E.L. Rakow at Lattice2003(matrix

Meson decay constants from Nf=2 clover fermions

We present recent results for meson decay constants calculated on configurations with two flavours of O(a)-improved Wilson fermions. Non-perturbative renormalisation is applied and quark mass dependencies as well as finite volume and discretisation effects are investigated. In this work we also present a computation of the coupling of the light vector mesons to the tensor current using dynamical fermions.Comment: 6 pages, contribution to Lattice2005(Hadron spectrum and quark masses

Molybdenum Disulfide Catalytic Coatings via Atomic Layer Deposition for Solar Hydrogen Production from Copper Gallium Diselenide Photocathodes

We demonstrate that applying atomic layer deposition-derived molybdenum disulfide (MoS2) catalytic coatings on copper gallium diselenide (CGSe) thin film absorbers can lead to efficient wide band gap photocathodes for photoelectrochemical hydrogen production. We have prepared a device that is free of precious metals, employing a CGSe absorber and a cadmium sulfide (CdS) buffer layer, a titanium dioxide (TiO2) interfacial layer, and a MoS2 catalytic layer. The resulting MoS2/TiO2/CdS/CGSe photocathode exhibits a photocurrent onset of +0.53 V vs RHE and a saturation photocurrent density of -10 mA cm-2, with stable operation for >5 h in acidic electrolyte. Spectroscopic investigations of this device architecture indicate that overlayer degradation occurs inhomogeneously, ultimately exposing the underlying CGSe absorber

Generalized Parton Distributions from Lattice QCD

We perform a quenched lattice calculation of the first moment of twist-two generalized parton distribution functions of the proton, and assess the total quark (spin and orbital angular momentum) contribution to the spin of the proton.Comment: 11 pages, 4 figures; final version, to be published in Phys. Rev. Let