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
Oh Dear! What Can the Matter Be? he'd buy me a fairing should please me, And then for a kiss, oh! he vowed he would tease me, He promised he'd bring me a bunch of blue ribbons, To tie up my bonny brown hair. </poem> Cohen's "Folk Music" gives a different version of the lyrics: <poem> O dear, what can the matter be? O dear, what can the matter be? O dear, what can the matter be? Johnny's so long at the fair. He promised he'd bring me a bunch of blue ribbons. He promised he'd bring me a bunch of blue ribbons. He promised he'd bring