What evidence supports the expansion of the universe?

The expansion of the universe is supported by several lines of evidence gathered from various scientific observations and measurements. One of the key pieces of evidence comes from the observations of distant galaxies. Scientists have observed that the light emitted by these galaxies is shifted towards longer wavelengths, known as redshift, which indicates that the galaxies are moving away from us. Moreover, the farther away a galaxy is, the larger its redshift is, suggesting that the expansion of the universe is occurring uniformly in all directions. This is known as the cosmological redshift and provides strong evidence for the expansion of the universe. Additionally, the cosmic microwave background radiation, a faint radiation permeating the entire cosmos, also helps confirm the expansion. The leftover radiation from the early universe exhibits slight temperature fluctuations, which are consistent with an expanding universe. Furthermore, other astrophysical measurements, such as the abundances of light elements and the distribution of galaxy clusters, also support the idea of an expanding universe. Together, these various lines of evidence help to substantiate the expansion of the universe as a fundamental aspect of our cosmic evolution.

This mind map was published on 27 October 2023 and has been viewed 57 times.