As an intermediate step, this chapter describes the quantization of the mechanical string. In order not to deal with the derivative in the potential energy density, a spatial Fourier transform is performed. Then, the procedure is quite analogously to the point-mechanical case, because the length of the string provides an extrinsic length parameter. Nevertheless, energy quanta, hω, emerge.
Keywords: Energy quantum, Extrinsic length parameter, Quantization, String.