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
First Draft of a Report on the EDVAC to denote a unit time delay, as time delays must be accounted for in a synchronous design. He points out that in one microsecond an electric pulse moves 300 meters so that until much higher clock speeds, e.g. 10 cycles per second (100 MHz), wire length would not be an issue. The need for error detection and correction is mentioned but not elaborated. A key design concept enunciated, and later named the Von Neumann architecture, is a uniform memory containing both numbers (data) and orders (instructions). "The device requires a considerable memory. While it appeared that various parts of this