We present cosmological constraints from a gravitational lensing mass map covering 9400 deg^{2}reconstructed from measurements of the cosmic microwave background (CMB) made by the Atacama Cosmology Telescope (ACT) from 2017 to 2021. In combination with measurements of baryon acoustic oscillations and big bang nucleosynthesis, we obtain the clustering amplitude
The Universe is neither homogeneous nor isotropic, but it is close enough that we can reasonably approximate it as such on suitably large scales.The inflationaryΛCold Dark Matter (ΛCDM) concordance cosmology builds on these assumptions to describe the origin and evolution of fluctuations. With standard assumptions about stressenergy sources, this system is specified by just seven phenomenological parameters,whose precise relations to underlying fundamental theories are complicated and may depend on details of those fields.Nevertheless, it is common practice to set the parameter that characterizes the spatial curvature, Ω
 Award ID(s):
 2013718
 NSFPAR ID:
 10475744
 Publisher / Repository:
 Journal of Cosmology and Astroparticle Physics
 Date Published:
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Volume:
 2023
 Issue:
 02
 ISSN:
 14757516
 Page Range / eLocation ID:
 049
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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