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← Beyond the horizon
06 / Foundations · 2 min

A universe with a history

The hot Big Bang model describes an early hot, dense universe that expanded and cooled.

In 30 seconds

  1. Expansion concerns distances on large cosmic scales.
  2. It is not simply debris exploding from one point into pre-existing empty space.
  3. The model does not by itself settle every question about an ultimate beginning.
Make it concrete

Mark dots along a stretchable line. Stretching increases distances between dots. The analogy illustrates separation, not the full geometry of the universe.

  1. 01Hot & dense
  2. 02Expansion
  3. 03Cooling
Concept diagram · simplified for learning
Check your understanding

Does the Big Bang model require Earth to be at the centre of expansion?

Learning paths →

Go to the source

Sources reviewed: 13.09.2026