ΛCDM

Lambda Cold Dark Matter Concordance Model

In recent years there has been an intensive study of the expanding universe and Hubble's Law. Many experiments and lines of modeling have contributed to the evaluation of the universe's expansion. After the earlier COBE and WMAP satellite data, the Planck satellite collected data for 4.5 years and as of 2020 provides the most accurate evaluation of the CMB radiation. The graphical history of Hubble's Law evaluation shown below is from the NASA publication on the Hubble Constant, H0.


Image Credit NASA

This plot compares values for H0 derived from a variety of methods. It includes 2016 and 2019 values from the distance ladder which builds from successive methods. It also includes a value from the observation of gravity waves, which is independent of that distance ladder.


Image Credit NASA

This plot compares values for H0 derived from the CMB only.

After the extensive data from the Planck satellite was received, the 2015 reports from the Planck Collaboration presented descriptive parameters for the universe in the ΛCDM concordance model:

Parameter
Measured Value
Normal Matter Density, Ωb0.0486 +/- 0.0003
Dark Matter Density, Ωc0.2589 +/- 0.0022
Space-Energy Density, ΩΛ0.6911 +/- 0.0062
Curvature Ωk (0 => flat)0.0008 +/- 0.0040
Hubble constant, H067.74 +/- 0.46 km/s/megaparsec
Age of the universe, Tuniv13.799 +/- 0.0040 billion years
Spectral Index, ns0.9667 +/- 0.0040


Newtonian model of expansion
Calculation of expansion time
How old is the universe?
Physical keys to cosmology
Index

NASA, Hubble Constant
 
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Index

Distance measurement

Reference:
 
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