We examine the gravitational redshift of radiation emitted from within the potential of a cluster. Spectral lines from the intracluster medium (ICM) are redshifted in proportion to the emission-weighted mean potential along the line of sight, amounting to approximately 50 km s-1 at a radius of 100 kpc h-1, for a cluster dispersion of 1200 km s-1. We show that the relative redshifts of different...

A 5×5 board is the smallest board on which one can set up all kind of chess pieces as a start position. We consider Gardner’s minichess variant in which all pieces are set as in a standard chessboard (from Rook to King). This game has roughly 9 × 10 legal positions and is comparable in this respect with checkers. We weakly solve this game, that is we prove its game-theoretic value and give a st...

Digital information is accumulating at an astounding rate, straining our ability to store and archive it. DNA is among the most dense and stable information media known. The development of new technologies in both DNA synthesis and sequencing make DNA an increasingly feasible digital storage medium. We developed a strategy to encode arbitrary digital information in DNA, wrote a 5.27-megabit boo...

The visual perception of contours by the brain is selective. When embedded within a noisy background, closed contours are detected faster, and with higher certainty, than open contours. We investigate this phenomenon theoretically with the paradigmatic excitable FitzHughNagumo model, by considering a set of locally coupled oscillators subject to local uncorrelated noise. Noise is needed to over...

We propose a new method of volume hologram multiplexing/demultiplexing in noncentrosymmetric media. Volume holograms may be multiplexed by tuning the material parameters of the recording medium (such as refractive index or lattice parameters) while keeping the external parameters (wavelength and angles) fixed. For example, an external dc electric field alters the index of refraction through the...

Iron and titanium form two known stable intermetallic compounds, FeTi and Fe2Ti. exists above 1000°C , decomposing to FeTi and T i below that temperature. We have briefly noted previousl;’ that one of these compounds, FeTi, will react directly with hydrogen to form a n easily decomposed hydride which may be useful as a hydrogen storage medium. Our primary purpose here is to discuss the Fe-Ti-H ...

T he topic of the “credit crunch” received considerable attention during the early 1990s. As a result, several initiatives aimed at eliminating regulatory disincentives to lending were put in place. For example, documentation requirements recently were reduced to the legal minimum for loans to small and medium-sized businesses. Also, examiners and bankers were encouraged to emphasize the charac...

We are interested in reaction-diffusion equations that model excitable media under the influence of an additive noise. In many models of this type, the homogeneous zero state is stable and interesting dynamics is observed only for certain initial data. In the presence of noise, the excitable media is stimulated and the noise may be sufficiently large to nucleate wave forms. In computations, we ...