Multiple Choice
Within which time frame from the initial Big Bang do cosmologists believe all four fundamental forces of nature were united into a single force?
A) t = 0 to 106 years, when radiation dominated the universe
B) t = 0 to 1 s, when photons interchanged freely with electron-positron pairs
C) t = 0 to 10-35 s, when the strong nuclear force "froze out" of the universe
D) t = 0 to 10-43 s, the Planck time, when gravity "froze out" of the universe
Correct Answer:
Verified
Correct Answer:
Verified
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