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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Definitions:

Equilibrium Price

The price at which the quantity of a good demanded by consumers equals the quantity supplied by producers, resulting in a stable market condition.

Decrease in Supply

A reduction in the availability of a particular good or service in the market.

Downward-Sloping Demand

A fundamental economic principle stating that, ceteris paribus, the quantity demanded of a good falls as the price of the good rises, illustrated by a downward-sloping demand curve.

Equilibrium Quantity

The quantity of goods or services supplied that is equal to the quantity demanded at the market equilibrium price.