The numerical investigation of wave propagation in the asymptotic domain of Kerr spacetime has only recently been possible thanks to the construction of suitable hyperboloidal coordinates. The asymptotics revealed an apparent puzzle in the decay rates of scalar fields: the late-time rates seemed to depend on whether finite distance observers are in the strong field domain or far away from the r...

to assess the interaction effects of weeds, sowing rate, and n splitting on dryland wheat yield, field experiments were conducted in two years (2007 and 2009) at the college of agriculture in shiraz university. the treatments were replicated four times and analyzed as a split- split plot in a randomized complete block. the weedy and weed free were treated as the main plots, the wheat sowing rat...

The differential conductance of NbN/GdN/TiN superconductor / ferromagnetic insulator / normal metal junctions, with a thick NbN layer shows a large zero-field voltage offset interpreted as a spin-filtered Zeeman splitting of the NbN density of states (DOS) by an effective exchange field (H0) from the GdN. The splitting increases linearly with applied field (Hext) enabling the relative sign of H...

Photon splitting is a QED process that can potentially suppress pair production in the inner magnetosphere of a pulsar with a super-strong magnetic field, and hence, may quench radio emission from these objects. While it is unknown how many splitting modes really operate in supercritical fields, we derive gap parameters of a high magnetic field pulsar for both the vacuum-type gap and the space-...

Given far field data of a time-harmonic wave radiated by an ensemble of well separated acoustic or electromagnetic sources as well as a priori information on the locations of these sources, we discuss an algorithm to approximate the far field data radiated by each of these sources separately. The method is based on a Galerkin procedure considering subspaces spanned by the singular vectors of “r...

Given a separable polynomial over a field, every maximal idempotent of its splitting algebra defines a representation of its splitting field. Nevertheless such an idempotent is not computable when dealing with a computable field if this field has no factorization algorithm for separable polynomials. Moreover, even when such an algorithm does exist, it is often too heavy. So we suggest to addres...