FIELD PRIMER · HOW A FIX IS KEPT GALACTIC STANDARD TIME
FIELD PRIMER · THE WHERE & THE WHEN

The Reckoning

A ship does not keep time — it reads it. Four dead giants fix the where; a net of spinning corpses keeps the when.

THE SPATIAL ANCHOR · WHERE

Space is three-deep, so three anchors are not enough — three only pin a plane, and a ship can sit above or below it with the same reading. One gives an origin; two an axis; three a flat sheet; a fourth, lifted off that sheet, closes the solid. Four dead giants in a tetrahedron — only then is depth real. A fifth is carried to catch the others lying. They outlast every empire — the only landmarks that keep still.

THE PULSAR CLOCK · WHEN

Dead stars that spin a thousand times a second, steadier than any clock a colony could forge. Read the phase of four — one for each unknown, x, y, z and the time t — and your place falls out of the same sum that gives the hour. The ship's clock only counts pulses between glimpses — it never keeps the time.

EPOCH ZERO
Pulse 0
struck at the reference surface of Sgr A*
THE BEACON
N + Δt
whole count, plus the light it took to arrive
✦ ◇ ✦

The Correction Stack

Raw pulses lie at speed. Six corrections, applied in order, before a fix can be trusted.

  1. 1Shapiroremove the lag of light bent past heavy bodies.
  2. 2Gravityundo the well the ship is sitting in.
  3. 3Velocitythe cruel one — needs the speed measured another way.
  4. 4Dopplerstrip the blue and red of the crossing.
  5. 5Spin-downthe pulsars tire; the catalogue knows how much.
  6. 6Solvenow the where and the when fall out, clean.
TWO CLOCKS, ALWAYS

What the crew ages by is not the hour of the sky.

Run hard toward the Hem and the ship's own time, τ, falls behind the standard, t. That gap is not a fault to mend — it is carried, reported, known before any rendezvous. A surveyor returning from the wreck-stars comes back genuinely time-displaced. The log records both.

τSHIP
PROPER
≠
tGALACTIC
STANDARD