Deep Neural Networks as Point Estimates for Deep Gaussian Processes

This section gives a brief overview of some of the useful properties of spherical harmonics. We refer the interested reader to Dai and Xu [55] and Efthimiou and Frye [56] for an in-depth overview. Spherical harmonics are special functions defined on a hypersphere and originate from solving Laplace's equation. They form a complete set of orthogonal functions, and any sufficiently regular function defined on the sphere can be written as a sum of these spherical harmonics, similar to the Fourier series with sines and cosines. Spherical harmonics have a natural ordering by increasing angular frequency.