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Openai/6946e998-79f0-8007-9a65-19828450838d
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==== 3. A plausible bell curve (in log space) ==== The natural way to make a βbell curveβ out of multiplicative factors spanning orders of magnitude is to treat logββ N as roughly normal: * Low tail: Nβ10N \approx 10Nβ10 β logββ N β 1 * High tail: Nβ5Γ107N \approx 5 \times 10^7Nβ5Γ107 β logββ N β 7.7 If you center the bell curve halfway in log-space (geometric mean of low and high), the peak lands at: * Mean logββ N β (1 + 7.7)/2 β 4.3 * So the peak N is around a few Γ 10β΄ intelligent-life planets over Galactic history. A simple Monte-Carlo using the low/mid/high values above (with mid more likely than extremes) gives something like: * Mean (in log-space): logββ N β 4.6 β N β 4Γ10β΄ * 1Ο range (~68%): - ~3Γ1033 \times 10^33Γ103 to 4Γ1054 \times 10^54Γ105 * 2Ο-ish range (~95%): - ~8Γ1028 \times 10^28Γ102 to ~2Γ1062 \times 10^62Γ106 * Extreme tails: - Down near N β 10 (all filters at pessimistic end) - Up near N β 5Γ10β· (all filters at optimistic end) If you actually drew this as a bell curve in logββ N: * The left tail would approach N β 10. * The right tail would approach N β 5Γ10β·. * The peak would sit around N β 10β΄β10β΅, i.e., tens of thousands of intelligent-life planets over the Milky Wayβs history.
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