2003/05/14 by Christoph Räth, C. Raeth, P. Schuecker
Mathematics · Physics and Astronomy · #Advanced Mathematical Theories and Applications #Amplitude #Artificial intelligence #Astrophysics #Computer science #Cosmic microwave background #Cosmology #Cosmology and Gravitation Theories #Gaussian #Mathematics #Minkowski space #Noise (video) #Non-Gaussianity #Optics #Physics #Quantum mechanics #Scale (ratio) #Scaling #Scientific Research and Discoveries #Spectral density #Statistical physics #Statistics #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2003.06799.x
17 pages, 12 figures, MNRAS, accepted for publication
arxiv created 2003/05/14 · openalex publication_date 2003/09/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate alternative methods to analyse CMB maps. Using the technique of constrained randomization, we construct surrogate maps which mimic both the power spectrum and the amplitude distribution of simulated CMB maps containing non-Gaussian signals. Analysing the maps with weighted scaling indices and Minkowski functionals yields in both cases statistically significant identification of the primordial non-Gaussianities. We demonstrate that the method is very robust with respect to noise. We also show that Minkowski functionals are able to account for non-linearities at higher noise level when applied in combination with surrogates than when only applied to noise added CMB maps and phase randomized versions of them, which only reproduce the power spectrum.