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  3. Dark Matter
Cosmology

Dark Matter

Definition

A hypothetical form of matter that does not emit, absorb, or reflect light. Its existence is inferred from gravitational effects on visible matter, such as galaxy rotation curves. Dark matter makes up about 27% of the universe's total mass-energy content.

Related Terms

Dark Energy

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

Galaxy

A gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. Galaxies range from ...

Gravitational Lensing

The bending of light from a distant source by the gravitational field of a massive intervening object. Predicted by gene...

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