What specific observation related to the CMB temperature led to the formulation of the Horizon Problem?

Answer

Opposite points on the sky lacking causal connection sharing the same temperature.

The Horizon Problem arises because opposite points on the sky, which have never had time to exchange light or energy, exhibit exactly the same temperature, implying they reached thermal equilibrium independently.

What specific observation related to the CMB temperature led to the formulation of the Horizon Problem?

#Videos

Cosmic Inflation Explained | Cosmology 101 Episode 6 - YouTube

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