The observed distribution of matter in the Universe is best understood as being caused by ____.
A) clumping of dark matter in the early Universe causing clumping of normal matter
B) clumping of normal matter in the early Universe causing clumping of dark matter
C) simultaneous clumping of normal and dark matter
D) large variations in the intensity of the cosmic microwave background
E) homogenous expansion of normal and dark matter

Question

Quizplus · Accepted Answer

Dark matter, which does not interact with electromagnetic forces, began to clump together due to gravitational forces in the early Universe. This clumping created gravitational wells into which normal (baryonic) matter later fell, leading to the formation of galaxies and larger structures. This process is supported by observations and simulations of cosmic structure formation.

The Observed Distribution of Matter in the Universe Is Best