Information Theoretic Bounds on Cosmic String Detection in CMB Maps with Noise

Autor:	Ciuca, Razvan, Hernández, Oscar F.
Rok vydání:	2019
Předmět:	Astrophysics - Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory
Druh dokumentu:	Working Paper
DOI:	10.1093/mnras/stz3551
Popis:	We use a convolutional neural network (CNN) to study cosmic string detection in cosmic microwave background (CMB) flat sky maps with Nambu-Goto strings. On noiseless maps we can measure string tensions down to order $10^{-9}$, however when noise is included we are unable to measure string tensions below $10^{-7}$. Motivated by this impasse, we derive an information theoretic bound on the detection of the cosmic string tension $G\mu$ from CMB maps. In particular we bound the information entropy of the posterior distribution of $G\mu$ in terms of the resolution, noise level and total survey area of the CMB map. We evaluate these bounds for the ACT, SPT-3G, Simons Observatory, Cosmic Origins Explorer, and CMB-S4 experiments. These bounds cannot be saturated by any method. Comment: v3: corrected error in table 1 entry for the CORE experiment. This matches the erratum submitted for the version published in MNRAS. 7 pages, 1 figure, 1 table
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1911.06378 Zobrazit plný text záznamu View this record from Arxiv