Wavenumber Wavenumber In the physical sciences, the wavenumber (also wave number or repetency) is the spatial frequency of a wave, measured in cycles per unit distance or radians per unit distance. Whereas temporal frequency can be thought of as the number of waves per unit time, wavenumber is the number of waves per unit distance. In multidimensional systems, the wavenumber is the magnitude of the wave vector. The space of wave vectors is called reciprocal space. Wave numbers and wave vectors play an essential role in optics and the physics of wave scattering, such as X-ray diffraction, neutron diffraction, and elementary
Shannon capacity of a graph no two of these code words can be confused with each other. By using this method, in "n" steps of communication, the sender can communicate up to 5 messages, significantly more than the 2 that could be transmitted with the simpler one-digit code. The effective number of values that can be transmitted per unit time step is (5) = . In graph-theoretic terms, this means that the Shannon capacity of the 5-cycle is at least . As showed, this bound is tight: it is not possible to find a more complicated system of code words that allows even more different