Amplification and Particle Creation B. L. Hu and K. Shiokawa Department of Physics, University of Maryland, College Park, MD 20742, USA (umdpp 97-125, submitted to Phys. Rev. D on July 29, 1997) We study novel effects associated with electromagnetic wave propagation in a Robertson-Walker universe and the Schwarzschild spacetime with a small amount of metric stochasticity. We find that localizat...

Central Pressure and Pulse Wave Amplification in the Upper Limb To the Editor: The important review of pulse pressure (PP) amplification1 was directed at better understanding of central (ascending aortic or carotid) pressure generated from upper limb measurements of cuff arterial pressure and pressure waveforms. One important issue, not addressed by the authors, is how 2 different noninvasive t...

Utilizing the underlying physics of evanescent-wave amplification by a negative-refractive-index slab, it is shown that evanescent waves with specific spatial frequencies can also be amplified without any reflection simply by two dielectric planar waveguides. The simple configuration allows one to take advantage of the high resolution limit of a high-refractive-index material without contact wi...

Until now, the analysis of long wave run-up on a plane beach has been focused on finding its maximum value, failing to capture the existence of resonant regimes. One-dimensional numerical simulations in the framework of the nonlinear shallow water equations are used to investigate the boundary value problem for plane and nontrivial beaches. Monochromatic waves, as well as virtual wave-gage reco...