2013/07/31 by Sigurd K. Næss, Sigurd K Næss, Thibaut Louis · 2 citations
Physics and Astronomy · #Convergence (economics) #Cosmic background radiation #Cosmic microwave background #Cosmology and Gravitation Theories #Fourier transform #Radio Astronomy Observations and Technology #Simple (philosophy) #Superconducting and THz Device Technology #Taylor series #Weak gravitational lensing #astro-ph.CO
paper · pdf · doi:10.1088/1475-7516/2013/09/001
published as JCAP 1309 (2013) 001 · 7 pages, 6 figures, submitted to JCAP
arxiv created 2013/08/03 · openalex publication_date 2013/09/02 · arxiv updated 2014/06/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Cosmic Microwave Background lensing simulation by Taylor expansion has long been considered impractical due to slow convergence, but a recent flat-sky implementation shows that a simple trick eliminates this problem, making Taylor lensing a fast and simple lensing algorithm for the flat sky. Here we generalize the method to the full sky, and study its convergence and performance relative to a commonly used numerical code, Lenspix, with extensive benchmarks of both. Compared to the flat sky case, the method takes a speed hit due to the slow speed of spherical harmonic transforms compared to fast Fourier transforms, resulting in speeds of 1/3 to 2/3 of Lenspix for similar accuracy.