We present cosmological constraints from a gravitational lensing mass map covering 9400 deg2reconstructed 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 inflationary-Λ-Cold Dark Matter (ΛCDM) concordance cosmology builds on these assumptions to describe the origin and evolution of fluctuations. With standard assumptions about stress-energy 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
- NSF-PAR 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:
- 1475-7516
- Page Range / eLocation ID:
- 049
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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