The Hubble Tension

The unresolved disagreement between measurements of the Hubble constant from the early and the local Universe.

Measurements of the expansion rate anchored in the early Universe (the CMB) give about 67 km/s/Mpc, while direct measurements in the nearby Universe give about 73 km/s/Mpc. The gap is now statistically significant and has resisted explanation as a simple error.

• Is the tension due to measurement systematics or new physics?
• Does it require modifying ΛCDM (e.g. early dark energy)?

• Related toThe Hubble Constant
• Related toThe Hubble Constant
• Part of modelThe Lambda-CDM Model
• Measured byHubble Space Telescope
• Measured byPlanck
• Associated withSH0ES
• Associated withEarly Dark Energy
• Associated withThe History of Cosmology