S2FFT computes Fourier transforms on the sphere and rotation group using JAX (ascl:2111.002) or PyTorch. It leverages autodiff to provide differentiable transforms, which are also deployable on hardware accelerators (e.g., GPUs and TPUs). More specifically, S2FFT provides support for spin spherical harmonic and Wigner transforms (for both real and complex signals), with support for adjoint transformations where needed, and comes with different optimisations (precompute or not) that one may select depending on available resources and desired angular resolution L.
Please see citation information here: https://github.com/astro-informatics/s2fft?tab=readme-ov-file#attribution-books