🔋college physics i – introduction review

GUT epoch

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

The GUT epoch is a period in the early universe, occurring between $10^{-43}$ and $10^{-36}$ seconds after the Big Bang, when the strong, weak, and electromagnetic forces were unified into a single force. It marks an important phase in cosmology where Grand Unified Theories (GUTs) are tested.

5 Must Know Facts For Your Next Test

  1. The GUT epoch occurred shortly after the Planck epoch and before the electroweak epoch.
  2. During this period, temperatures were around $10^{27}$ Kelvin.
  3. It is theorized that during the GUT epoch, the universe transitioned from being dominated by quantum gravity to being dominated by fundamental forces as we know them today.
  4. Grand Unified Theories attempt to merge three of the four fundamental forces: strong nuclear, weak nuclear, and electromagnetic forces.
  5. Symmetry breaking during this epoch led to the separation of these forces and set conditions for subsequent epochs.

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