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Dark Matter

Dark matter is a hypothetical form of matter thought to be the predominant type of matter in the universe. It is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not absorb, reflect, or emit electromagnetic radiation and is, therefore, difficult to detect. Its existence is implied by various astrophysical observations which cannot be explained by General Relativity unless more matter is present than can be seen. Evidence for dark matter comes from many different angles, such as galaxy dynamics and formation, gravitational lensing, and the cosmic microwave background, along with astronomical observations of the observable universe's current structure, the formation and evolution of galaxies, mass location… more »