We apply a new formalism to calculating emission of light from sheared dielectric surfaces. When the surfaces are smooth, the emission of light requires extreme velocities, but introducing surface roughness with short-period components reduces the extreme demands on velocity so that, for atomic-scale roughness, shear velocities as small as 104ms-' will result in light emission. Some order-of-ma...

We experimentally demonstrate wideband dispersion-free slow light in chirped photonic crystal coupled waveguides (PCCW). In unchirped PCCWs, the zero group velocity can occur at an inflection point of a photonic band of even symmetric mode. The even symmetric mode is selectively excited by connecting the device with input and output waveguides through optimized branch and confluence structures....

We analyze a transition from single peaked to bimodal velocity distribution in a relativistic fluid under increasing temperature, in contrast with a non-relativistic gas, where only a monotonic broadening of the bell-shaped distribution is observed. Such transition results from the interplay between the raise in thermal energy and the constraint of maximum velocity imposed by the speed of light...

A measurement of the drift velocity of free electrons in liquid argon has been performed. Free electrons have been produced by photoelectric e ect using laser light in a so called \laser chamber". The results on the drift velocity vd are given as a function of the electric eld strength in the range 0:5 kV=cm j ~ Ej 12:6 kV=cm and the temperature in the range 87 K T 94 K. A global parametrizatio...

The threading of a polymer chain through a small pore is a classic problem in polymer dynamics and underlies nanopore sensing technology. However important experimental aspects of the polymer motion in a solid-state nanopore, such as an accurate measurement of the velocity variation during translocation, have remained elusive. In this work we analysed the translocation through conical quartz na...

Some of the Galactic outer halo globular clusters are excellent tools to probe gravitational theories in the regime of weak accelerations (Baumgardt et al. 2005). The measurement of the line-of-sight velocity dispersion among stars in these clusters will differentiate between the validity of Newtonian dynamics (low velocity dispersion) and the possiblity of modified Newtonian dynamics (MOND) or...

Up to now little attention has been paid to an expression for the velocity of light in a gravitational field derived by Einstein in 1911. It is shown that (i) this expression represents the proper velocity of light (since it is defined in terms of proper time and length), (ii) the proper velocity of light is anisotropic in non-inertial reference frames, and (iii) unlike the coordinate velocity ...

An innovative Volumetric Current Meter (VCM) was designed in order to allow quick velocity measurements in open channels. At first, the coefficient of velocity (Cv) of the device was determined through calibration under different water velocities in the laboratory. The measurement performance was verified by measurements performed in similar flows in irrigation channels using an ordinary curren...