Paper № I · Network science · 2026 · 50 pages
4.6 Degrees of Separation
Pick any two people on Earth. The introductions between them fall short of the famous six, and barely move as the network grows.
Sample entry Seeded from real work while the archive is under construction. The published paper replaces it.
The number six is a literary inheritance. It enters the world in 1929, in a Frigyes Karinthy short story, as a bet that any of Earth’s 1.5 billion people could be reached through five intermediaries. Milgram’s 1967 letter experiment made it famous; the audits that followed made it shakier.
This paper measures the real distances. Eight networks measured directly, one of them exactly, across three hundred million pairs. A regression-calibrated model fitted to the empirical record, cross-validated, and pushed to its limit on the global human social graph. The number it converges to is 4.6.
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