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Cosmology

Hubble Constant

Definition

A value describing the rate of the universe's expansion, named after Edwin Hubble. Its precise value remains debated, with the discrepancy between measurement methods known as the Hubble tension being a major unsolved problem in cosmology.

Related Terms

Big Bang

The prevailing cosmological model explaining the origin of the universe from an initial state of extremely high density ...

Dark Energy

A hypothetical form of energy that permeates all of space and drives the accelerating expansion of the universe. It cons...

Redshift

An increase in wavelength of radiation from an object moving away from the observer. The redshift of distant galaxies pr...

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