The spherical harmonic transform (SHT) is probably the most important tool in the field of CMB analysis. The past months I've been working on a code that speeds up computation of spherical harmonic transforms (SHTs) by a factor of between 2 and 6 (see here). I will:
- Give a basic introduction to what spherical harmonic transforms are and what they're used for in cosmological data analysis
- Give the basic intuition (skipping a lot of details) for an exciting algorithm for "compressing" a certain class of linear operators. The method is related both to methods used in N-body simulations and methods for solving certain partial differential equations.
- A few words on software development: What Python is and why I used it, test-driven development, how optimizing code to make it faster was not at all the process I expected it to be.