The Crossover Point from Radiation to Matter Domination Occurred

question 44

Multiple Choice

The crossover point from radiation to matter domination occurred:

• A) when the strong force separated from the other two forces.
• B) with the emission of the cosmic background radiation.
• C) about 50,000 years after the Big Bang, at a temperature of about 16,000 K.
• D) with the creation of neutrons and protons, at about 10¹³ K.
• E) with the creation of electrons and positrons at about 6 × 10⁹ K.

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