Question

P29.4 It has taken roughly 13.75 Gy for the light from the CMB to reach us. But how far is the matter emitting the CMB away from us at present? This is the distance that we want to compare with the 10,000-Gly distance mentioned in the section “Solving the Horizon Problem.” (Hint: The result is not 13.75 Gly: there is a big difference between the cosmic time t and the cosmic time parameter 1.)

Answer 1

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