1.3 Dark Matter History Summary

summary

Even back in Antiquity, people wanted to understand the universe’s origins.
The origins of our modern understanding of cosmology date back to Einstein in 1915.
Einstein hypothesized that the universe could be in one of three states: expanding, contracting, or remaining the same size.
In the 1920s, Edwin Hubble showed that most galaxies are moving away from our galaxy, the Milky Way.
After the Big Bang, the universe cooled and then expanded.
All of the atomic material adds up to only 5% of the universe; dark matter comprises 25%, and dark energy 70%.
The problem of dark matter dates back to 1930, when Knut Lundmark and Fritz Zwicky observed that rapid motions of galaxies could only be explained if dark matter exists.
In the 1970s, Vera Rubin and Kent Ford, in order to explain the velocities of stars in galaxies, showed that dark matter must exist in every galaxy.