Fisher forecasts for primordial non-Gaussianity from persistent homology. Issue 10 (1st October 2022)

• Record Type: Journal Article
• Authors: Biagetti, Matteo; Calles, Juan; Castiblanco, Lina; Cole, Alex; Noreña, Jorge
• Is Part Of: Journal of cosmology and astroparticle physics. Volume 2022:Issue 10(2022)
• Publication Date: 2022-10-01
• Subjects: cosmic web -- cosmological simulations -- galaxy clustering -- physics of the early universe; Cosmology -- Periodicals; Astrophysics -- Periodicals; 523.0105
• DOI: 10.1088/1475-7516/2022/10/002
• Languages: English
• ISSNs: 1475-7516

Abstract

Abstract: We study the information content of summary statistics built from the multi-scale topology of large-scale structures on primordial non-Gaussianity of the local and equilateral type. We use halo catalogs generated from numerical N-body simulations of the Universe on large scales as a proxy for observed galaxies. Besides calculating the Fisher matrix for halos in real space, we also check more realistic scenarios in redshift space. Without needing to take a distant observer approximation, we place the observer on a corner of the box. We also add redshift errors mimicking spectroscopic and photometric samples. We perform several tests to assess the reliability of our Fisher matrix, including the Gaussianity of our summary statistics and convergence. We find that the marginalized 1- σ uncertainties in redshift space are Δ f NL loc ∼ 16 and Δ f NL equi ∼ 41 on a survey volume of 1 (Gpc/ h ) 3 . These constraints are weakly affected by redshift errors. We close by speculating as to how this approach can be made robust against small-scale uncertainties by exploiting (non)locality.