X-wave
Encyclopedia
In physics
, X-waves are localized solutions of the wave equation
that travel at a constant velocity
in a given direction. X-waves can be sound, electromagnetic, or gravitational wave
s. They are built as a non-monochromatic superposition
of Bessel beam
s. X-waves carry infinite energy
. Electromagnetic X-waves travel faster than the speed of light. Finite-energy realizations have been observed in various frameworks.
In optics, X-waves solution have been reported within a quantum mechanical formulation.
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
, X-waves are localized solutions of the wave equation
Wave equation
The wave equation is an important second-order linear partial differential equation for the description of waves – as they occur in physics – such as sound waves, light waves and water waves. It arises in fields like acoustics, electromagnetics, and fluid dynamics...
that travel at a constant velocity
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...
in a given direction. X-waves can be sound, electromagnetic, or gravitational wave
Gravitational wave
In physics, gravitational waves are theoretical ripples in the curvature of spacetime which propagates as a wave, traveling outward from the source. Predicted to exist by Albert Einstein in 1916 on the basis of his theory of general relativity, gravitational waves theoretically transport energy as...
s. They are built as a non-monochromatic superposition
Superposition principle
In physics and systems theory, the superposition principle , also known as superposition property, states that, for all linear systems, the net response at a given place and time caused by two or more stimuli is the sum of the responses which would have been caused by each stimulus individually...
of Bessel beam
Bessel beam
A Bessel beam is a field of electromagnetic, acoustic or even gravitational radiation whose amplitude is described by a Bessel function of the first kind. A true Bessel beam is non-diffractive. This means that as it propagates, it does not diffract and spread out; this is in contrast to the usual...
s. X-waves carry infinite energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...
. Electromagnetic X-waves travel faster than the speed of light. Finite-energy realizations have been observed in various frameworks.
In optics, X-waves solution have been reported within a quantum mechanical formulation.
External links
- The Virtual Institute for Nonlinear Optics (VINO), a research collaboration devoted to the investigation of X-waves and conical waves in general
- Nolinear X-waves page at the nlo.phys.uniroma1.it website.