21 Waves in Cold Plasmas: Two-Fluid Formalism 1 21.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 21.2 Dielectric Tensor, Wave Equation, and General Dispersion Relation . . . . . 3 21.3 Two-Fluid Formalism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 21.4 Wave Modes in an Unmagnetized Plasma . . . . . . . . . . . . . . . . . . . . 7 2...

We present an elementary method to obtain the equations of the shallow-water solitary waves in different orders of approximation. The first two of these equations are solved to get the shapes and propagation velocities of the corresponding solitary waves. The first order equation is shown to be equivalent to the Korteweg−de Vries (KdV) equation, while the second order equation is solved numeric...

This paper presents a new theory of radiation and propagation of electromagnetic (EM) waves: EM waves caused by the same cause will never cross each other. It discloses a fundamental mistake in the established assumptions and method of analysis of radiation and propagation problems of electromagnetic waves and application of superposition principle. It implies invalidation of the established so...

The problems under consideration are related to wave propagation in nonlinear dispersive media, characterised by higher-order nonlinear and higher-order dispersive effects. Particularly two problems — wave propagation in dilatant granular materials and wave propagation in shape-memory alloys — are studied. Model equations are KdVlike evolution equations in both cases. The types of solutions are...

Under certain circumstances, Voigt waves can propagate in a biaxial composite medium even though the component material phases individually do not support Voigt wave propagation. This phenomenon is considered within the context of the strong– permittivity–fluctuation theory. A generalized implementation of the theory is developed in order to explore the propagation of Voigt waves in any directi...

Ultrasonic wave propagation in water-saturated bovine cancellous (spongy) bone has been experimentally studied in vitro by a pulse transmission technique. In earlier investigation, fast and slow longitudinal waves have been clearly observed when the acoustic wave propagates in the direction of the trabeculm orientation. In the present study, the propagation speeds of the fast and the slow waves...

The anisotropic materials as the acoustic wave propagating medium introduce the dependence of the phase velocity on the wave propagation direction, as opposed to the isotropic counterparts; in addition, the profile of the particle displacement components can be quite different, depending on the crystal type and propagation direction. The propagation of surface and bulk acoustic waves (SAWs and ...

In cancellous bone, longitudinal waves often separate into fast and slow waves depending on the alignment of bone trabeculae in the propagation path [1]. This interesting phenomenon becomes an effective tool for the diagnosis of osteoporosis because wave propagation behavior depends on the bone structure [2]. Nagatani et al. pointed that fast wave requires certain propagation distance for stead...

Gravitational waves, as predicted by Einstein's general relativity theory, appear as ripples in the fabric of spacetime traveling at the speed of light. We prove that the propagation of small amplitude gravitational waves in a curved spacetime is equivalent to the propagation of a subspace of electromagnetic states. We use this result to propose the use of entangled photons to emulate the evolu...

This paper concerns the description of surface water waves, specifically nonlinear changes in the directionality. Supporting calculations are provided to establish the best method of directional wave generation, the preferred method of directional analysis and the inputs on which such a method should be based. These calculations show that a random directional method, in which the phasing, ampli...