There are good indications that fundamental physics gives rise to a modified spacemomentum uncertainty relation that implies the existence of a minimum length scale. We implement this idea in the free scalar field theory that describes density perturbations in flat Robertson-Walker space-time. This leads to a non-linear timedependent dispersion relation that encodes the effects of Planck scale ...

Thermally excited waves in a Plasma crystal were numerically simulated using a Box_Tree code. The code is a Barnes_Hut tree code proven effective in modeling systems composed of large numbers of particles. Interaction between individual particles was assumed to conform to a Yukawa potential. Particle charge, mass, density, Debye length and output data intervals are all adjustable parameters in ...

Article history: Received 7 April 2011 Received in revised form 17 September 2011 Accepted 18 September 2011 Is wind direction an adequate marker of air mass history? This review looks at the evolution of methods for assessing the effect of the origin and pathway of air masses on composition change and trends. The composition of air masses and how they evolve and the changing contribution of so...

We discuss the linear dispersive properties of finite one-dimensional photonic band-gap structures. We introduce the concept of a complex effective index for structures of finite length, derived from a generalized dispersion equation that identically satisfies the Kramers-Kronig relations. We then address the conditions necessary for optimal, phase-matched, resonant second harmonic generation. ...

Fitness landscape analysis provides insight into the structural features of optimization problems. Landscape analysis techniques have been individually shown to capture specific continuous landscape features. However, results are typically for benchmark and artificial problems, and so the ability of techniques to capture real-world problem structures remains largely unknown. In this paper we ex...

The dispersion of carbon black agglomerates suspended in polydimethyl siloxane (PDMS) or polybutadiene (PBD) liquids has been studied. Agglomerates comprised of either a low-structure or a high-structure carbonblack were subjected to simple shear flow. Two characteristic length scales that affect the dispersion process are identified. One length scale (Lp) is a measure of the ease with which fl...

certain coherent displacements did indeed linearly perturb the dispersion. This observation led to several studies of systematic’ and random8 errors with the conclusion that this effect stems from the fact that the dispersion in the Arcs is not always matched (especially in the vertical plane) due to the necessity of rolling the achromats about the beam axis to follow the site terrain. We will ...

Dispersion quantifies the impact of subscale velocity fluctuations on the effective movement of particles and the evolution of scalar distributions in heterogeneous flows. Which fluctuation scales are represented by and what is the meaning of dispersion, depends on the definition of the subscale, or the corresponding coarse graining scale. We study here the dispersion effect due to velocity flu...

Laser-induced fluorescence was used to measure the lateral dispersion of passive solute in random arrays of rigid, emergent cylinders of solid volume fraction φ=0.010– 0.35. Such densities correspond to those observed in aquatic plant canopies and complement those in packed beds of spheres, where φ 0.5. This paper focuses on pore Reynolds numbers greater than Res =250, for which our laboratory ...

Numerical simulation of seismic waves is essential for understanding field observations and developing inversion schemes. The wavefields generated by the most popular numerical methods such as finite differences and finite elements are often contaminated with grid dispersion and edge reflections. We will present a grid dispersion and stability analysis based on a generalized eigenvalue formulat...