Lambda-CDM model

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Lambda-CDM model" – news · newspapers · books · scholar · JSTOR (February 2024) (Learn how and when to remove this message)

Part of a series on
Physical cosmology
Big Bang · Universe Age of the universe Chronology of the universe
Early universe Inflation · Nucleosynthesis Backgrounds Gravitational wave (GWB) Microwave (CMB) · Neutrino (CNB)
Expansion · Future Hubble's law · Redshift Expansion of the universe FLRW metric · Friedmann equations Lambda-CDM model Future of an expanding universe Ultimate fate of the universe
Components · Structure Components Dark energy · Dark matter Photons · Baryons Structure Shape of the universe Galaxy filament · Galaxy formation Large quasar group Large-scale structure Reionization · Structure formation
Experiments Black Hole Initiative (BHI) BOOMERanG Cosmic Background Explorer (COBE) Dark Energy Survey Planck space observatory Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey ("2dF") Wilkinson Microwave Anisotropy Probe (WMAP)
Scientists Aaronson Alfvén Alpher Copernicus de Sitter Dicke Ehlers Einstein Ellis Friedmann Galileo Gamow Guth Hawking Hubble Huygens Kepler Lemaître Mather Newton Penrose Penzias Rubin Schmidt Smoot Suntzeff Sunyaev Tolman Wilson Zeldovich List of cosmologists
Subject history Discovery of cosmic microwave background radiation History of the Big Bang theory Timeline of cosmological theories
Category Astronomy portal
v t e

The Lambda-CDM, Lambda cold dark matter, or ΛCDM model is a mathematical model of the Big Bang theory with three major components:

1. a cosmological constant, denoted by lambda (Λ), associated with dark energy;
2. the postulated cold dark matter, denoted by CDM;
3. ordinary matter.

It is the current standard model of Big Bang cosmology,^[1] as it is the simplest model that provides a reasonably good account of:

• the existence and structure of the cosmic microwave background;
• the large-scale structure in the distribution of galaxies;
• the observed abundances of hydrogen (including deuterium), helium, and lithium;
• the accelerating expansion of the universe observed in the light from distant galaxies and supernovae.

The model assumes that general relativity is the correct theory of gravity on cosmological scales. It emerged in the late 1990s as a concordance cosmology, after a period of time when disparate observed properties of the universe appeared mutually inconsistent, and there was no consensus on the makeup of the energy density of the universe.

The ΛCDM model has been successful in modeling broad collection of astronomical observations over decades. Remaining issues have lead to many alternative models and challenges the assumptions of the ΛCDM model.^[2]