The Diode That Remembers · Gate & Store In One

The Triadic Memristor

one two-terminal element gates AND remembers · trusted by 2-of-3

Swap the diode out. A memristor — Chua's 1971 fourth element, made real by HP in 2008 — is a single two-terminal device that does both jobs at once: write polarity switches it (the gate) and it retains its resistance with the power off (the store). So the toroid and its nine diodes collapse into three memristors — and the read is now non-destructive. The same 2-of-3 witness, one element per node.

{ ▭J1[R-state = bit]   ▭J2[R-state = bit]   ▭J3[R-state = bit] }  ·  gate + store = 1 device × 3
write a bit — voltage polarity SETs or RESETs all three memristors. read it back (the small read voltage doesn't disturb the state), or drift one and heal it.
// memristor log — every SET/RESET, non-destructive read, and quorum decision
V I
the fingerprint: a memristor's I–V curve is a pinched hysteresis loop — two lobes crossing at the origin (zero voltage → zero current, always). The loop area IS the memory: the current depends not just on the voltage now, but on all the charge that came before. Chua's signature of the fourth element.

One Element, Both Jobs

gate + store, fused
The bit is the memristor's resistance state — low-R (SET, "1") or high-R (RESET, "0"). Write polarity switches it (the diode's one-way job) and it retains the state with no power (the toroid's job). Two devices become one.
non-destructive read
Unlike core memory, reading doesn't erase. A small read voltage below the switching threshold measures the resistance without moving the state. Read all you like; the bit stays. A real gain over the toroid.
the honest tax
Real memristors have finite endurance (writes wear them) and drift/variability. And in a crossbar, sneak-path currents force a selector (a diode or transistor) back into each cell — 1D1R / 1T1R. The diode doesn't fully vanish at scale.
3 memristors = the minimum self-verifying memory in one device per node. Each remembers its own bit; 2-of-3 outvotes a single drifted cell. The Triadic Core's toroid-plus-diodes, collapsed to a single two-terminal element — Chua 1971, HP 2008, the basis of ReRAM.
honest line: the memristor genuinely fuses gate and store and makes the read non-destructive — a real improvement on the core version. But the same fault bound holds: with a single bit, three cells always have a majority, so two cells drifted the same way silently flip the trusted value (2-of-3 masks one fault). And the device is real but imperfect — endurance, drift, and sneak-path selectors are the standing caveats. The witness is unchanged; only the element got better.
MEMRISTOR = CHUA'S 4TH ELEMENT (1971) · HP TiO₂ (2008) · BIT = RESISTANCE STATE (LOW-R=1 / HIGH-R=0)
WRITE POLARITY SWITCHES (THE GATE) · STATE RETAINED WITH NO POWER (THE STORE) · READ IS NON-DESTRUCTIVE
3 MEMRISTORS · 2-OF-3 WITNESS · ONE DRIFT HEALED · TWO SAME-WAY = SILENT (TMR MASKS ONE FAULT)
THE TRIADIC MEMRISTOR · A BUILD-ON OF THE TRIADIC CORE · SERIES E · JUNE 2026