What is the role of dark matter in the universe's evolution?.

Dark matter is an unseen substance that does not emit, absorb, or reflect light, making it invisible and detectable only through its gravitational effects. It plays a pivotal role in the evolution of the universe by:

Key Facts

• Composition: Dark matter constitutes approximately 27% of the universe's total mass-energy content.
• Galaxy Formation: It provides the gravitational scaffolding necessary for the formation of galaxies and galaxy clusters.
• Cosmic Web: Dark matter contributes to the formation of the cosmic web, influencing the distribution of galaxies across the universe.
• Detection Methods: Scientists infer the presence of dark matter through gravitational lensing, cosmic microwave background radiation, and galaxy rotation curves.

Examples or Use Cases

• In simulations, dark matter is modeled to understand the large-scale structure of the universe, explaining the clustering of galaxies and the voids in between.
• Observations of the Bullet Cluster provided significant evidence for dark matter, showing how its gravitational influence differs from ordinary matter.

FAQs

• What evidence supports the existence of dark matter? Observational evidence from galaxy rotations, gravitational lensing, and cosmic background radiation supports dark matter's existence.
• Can dark matter be directly detected? Currently, dark matter has not been directly detected; it is inferred from its gravitational effects on visible matter.