Suppose a hypothetical universe is expanding (at some moment in time) at a rate of H. At this same moment the density of this Universe is ρ. (a) Confirm for yourself that this is a closed universe, given the values below. (b) Determine, and enter below, the spatial radius of curvature for this closed universe (at the same moment in time at which the values above are given). Values: H = 56 km s-1 Mpc-1 ρ = 4.9x10-25 kg m-3 Give your answer for (b) in units of Mpc, to the nearest integer (not in scientific notation - e.g., 1234).
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Suppose a hypothetical universe is expanding (at some moment in time) at a rate of H. At this same moment the density of this Universe is ρ.
(a) Confirm for yourself that this is a closed universe, given the values below.
(b) Determine, and enter below, the spatial radius of curvature for this closed universe (at the same moment in time at which the values above are given).
Values:
H = 56 km s-1 Mpc-1
ρ = 4.9x10-25 kg m-3
Give your answer for (b) in units of Mpc, to the nearest integer (not in scientific notation - e.g., 1234).
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