wave vector

A wave vector is a vector that specifies the wavenumber and direction of propagation for a wave. The magnitude of the wave vector indicates the wavenumber. The orientation of the wave vector indicates the direction of wave propagation. For example consider a plane wave. A common representation of the oscillation at time (t) and a single point in space (z) along the direction of propagation is: where A is the amplitude, φ is the starting phase of the wave, k is the angular wavenumber, and ω is the angular frequency. We can easily extend the formula by substituting the dot product of the wave vector k and the position vector r for the scalar product of the wavenumber k and the variable z as follows:.
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