A New Tripoli resident can opt into running faster than real time. Pick a dilation rate and see how much subjective life you live per real second — and what that does to the gap between Universal Sabbaths, and to the number of people you can ever meet.
Roughly every six months of real time, the Human Server Stadium performs scheduled maintenance — hardware checks, cooling system service, reorientation of substrate units to reflect relationship changes. During this window, all residents are automatically "hearthed" back to their home and every speed tier is returned to 1× simultaneously. No one can move outside their home for the duration (~1 hour real time).
This is the only moment in New Tripoli when everyone shares the same present. A resident running at 50,000× and a resident running at 1× are, for those few hours, at the same instant. Live video calls become possible across all speed gaps. Friends and family who run at wildly different rates can have a real conversation — not letters, but a conversation.
Characters describe the approach of a Sabbath window the way pre-Intake cultures described major holidays: as something to prepare for, compose yourself toward, write the letter you've been putting off. For residents at extreme dilation rates, it arrives very rarely by subjective measure — a 1,000× resident experiences 500 subjective years between windows. The Sabbath is called "universal" not as a metaphor but as a literal fact: it is, briefly, universal.
New Tripoli dilation is a pure clock-rate multiplier. At rate R×, you experience R subjective seconds for every one real (Earth-Prime / HSS 1×) second:
subjective time = R × real time
So per real year you live R subjective years; per six-month maintenance interval you live R × 0.5 subjective years. New Centauri's million-fold rate is exactly the canon line "a million subjective years per calendar year."
At maintenance (§9), every resident is briefly returned to 1× simultaneously — the only moment all speed tiers share a present. The faster you run, the longer the subjective wait between those moments. A 1,000× resident lives ~500 subjective years between two 6-month windows; this is the canon's inverse loneliness problem — synchrony with slower friends becomes rare and precious. It is also why the max coherent sim-story length equals this same figure: a sim can't tell a story longer than the block before everyone is hearthed home. New Tripoli's 50× ceiling over 6 months gives the canon's 25-simulated-year cap.
The "people met" figure is illustrative — it multiplies your chosen meeting rate by the subjective years you live in one real year. The caps are real estimates: Dunbar's number (~150 stable relationships), the Bernard–Killworth network estimate (~230–290), and a rough lifetime-acquaintance cap (~600). Even modest dilation blows past all three, which is the §30 premise: AI contact-triage exists because no human social faculty was built for this.
Great apes are capped at 2× (a few robust chimps reach 4×) against the human 50× ceiling. The "Ape ceiling · 2×" preset shows why Ham and Enos are gradually left behind: at 2× they live one subjective year per six real months, while their human friends at 50× live twenty-five.
Sister tool in the linked scenario: the OCS Gravitational Time Dilation Comparator derives the same subjective-time speedup from the Schwarzschild metric instead of a substrate setting. Both worlds share the Transcension Hypothesis lineage (see Cognitive Husbandry.md, "On ETI Motivation").
Further reading: Hafele, J.C., & Keating, R.E. (1972). "Around-the-World Atomic Clocks: Observed Relativistic Time Gains." Science, 177(4044), 166–170 — the experiment that empirically confirmed Einstein's time dilation: atomic clocks flown around the Earth on commercial jets ran measurably differently from stationary ones. Dunbar, R.I.M. (1992). "Neocortex size as a constraint on group size in primates." Journal of Human Evolution, 22(6), 469–493 — the original paper establishing the ~150-relationship cognitive limit that New Centauri's dilation rate renders catastrophically obsolete.