Sufficient conditions for wave breaking are found for the short-pulse equation describing wave packets of few cycles on the ultra-short pulse scale. The analysis relies on the method of characteristics and conserved quantities of the short-pulse equation and holds both on an infinite line and in a periodic domain. Numerical illustrations of the finite-time wave breaking are given in a periodic ...

We present a photonic wave packet construction which is immune against the decoherence effects induced by the action of the Lorentz group. The amplitudes of a pure quantum state representing the wave packet remain invariant irrespective of the reference frame into which the wave packet has been transformed. Transmitted information is encoded in the helicity degrees of freedom of two correlated ...

A time-dependent wave packet method has been employed to calculate the state-to-state reaction probability for the H1H2O~0,0,0!→H2~v1 , j1!1OH~v2 , j2! reaction for J50 and initial nonrotating H2O on the modified Schatz–Elgersman potential energy surface in full six dimensions ~6D!. Starting from a wave packet for an atom–triatom asymptotic state in atom–triatom Jacobi coordinates, we transfer ...

The spreading of quantum mechanical wave packets are studied in two cases. Firstly we look at the time behavior of the packet width of a free particle confined in the observable Universe. Secondly, by imposing the conservation of the time average of the packet width of a particle driven by a harmonic oscillator potential, we find a zero-point energy which frequency is the de Broglie frequency. ...

In this paper we develop a higher-order nonlinear Schrodinger equation with variable coefficients to describe how a water wave packet will deform and eventually be destroyed as it propagates shoreward from deep to shallow water. It is well-known that in the framework of the usual nonlinear Schrodinger equation, a wave packet can only exist in deep water, more precisely when kh > 1.363 where k i...

The paper gives a symplectic-geometric account of semiclassical Gaussian wave packet dynamics. We employ geometric techniques to “strip away” the symplectic structure behind the time-dependent Schrödinger equation and incorporate it into semiclassical wave packet dynamics. We show that the Gaussian wave packet dynamics of Heller is a Hamiltonian system with respect to the symplectic structure, ...

Recently we reported a series of numerical simulations proving that it is possible in principle to create an electronic wave packet and subsequent electronic motion in a neutral molecule photoexcited by a UV pump pulse within a few femtoseconds. We considered the ozone molecule: for this system the electronic wave packet leads to a dissociation process. In the present work, we investigate more ...

If nonhydrostatic internal waves are of sufficiently large amplitude, they undergo significant dispersion due to interactions between the waves and wave-induced mean flow. The effect of these interactions is investigated for internal waves propagating upward in a uniformly stratified Boussinesq flow with uniform shear. The sign of the shear is established so that the wave intrinsic frequency in...