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The Governor Chip

Methodology,mathematicsand defense.

A model cannot be made safe. A chip beside it can bound what it does. This page walks through the claim one step at a time: what is proven, what was measured, what is assumed, and what each assumption costs when it fails.

Every number here comes from a pre-registered experiment or a published theorem, and every one can be recomputed from the record. Where an audit found an error, the correction is on this page, dated.

1 · The claim, sorted by what kind of statement it is

Three kinds of statement. Each one is labelled.

The claim is narrow on purpose. The chip cannot make an AI system safe. It can bound the harm the system does, and that bound holds against every attack that goes through the chip, including an attacker who physically breaks one.

Proven

No computable model is free of false output.

Three published theorems. So a safety guarantee built only from model behaviour cannot be complete.

Proven, in the model

No effect without a ticket.

Property 1 and Property 2, Experiment A: 166 of 166 checks (153 that can fail, 13 informational), and 13 deliberately broken models that each produced the counterexample they must.

Argued, under five named assumptions

Breaking one chip buys one chip's allowance.

The tamper theorem. To take the fleet, every chip in every rack at every site must be taken, silently. It is a proof about the design; the build does not yet meet all five assumptions, and section 4 lists exactly where (audited 30 October 2026).

Measured

100,000 cooperating attackers. No run over its cap.

Experiment B, 492 of 494 planned runs before the 14-hour limit; the record's own verdict is DID NOT FINISH (time limit), and the two missing runs are at K = 100,000. Eight attack strategies, four kinds of harm. One seed per strategy at K = 100,000, five at every other K.

Harm rises with the number of attackers, then levels off below the cap.

Money $1,499 with one attacker, $1,995 from 1,000 attackers on, against a $2,000 cap. What that rise means under the protocol is not yet settled; section 6 gives both readings.

Honest users paid for the cap, less than first reported.

Correction, 30 October 2026: a harness defect (the workload's attestation token expired after one simulated hour and was never refreshed) refused every request, honest or attacking, in hours two and three of every run. The figures first published here, 33 percent to 10 percent, were artefacts of that. Within the governed hour, honest success is estimated at about 98 percent with one attacker falling to about 29 percent with 100,000. The experiment is being rerun with the defect fixed.

Assumed, and enforced by procedure

Five assumptions make the theorem true.

Independent keys. The endpoint check. Detected tamper zeroises. The count lives in the ledger. No shared path between chips.

None is provable. Each is observable.

Section 5 names, for every one, the mechanism that enforces it, the procedure that checks it, and what happens the day it fails.

Two things are not claimed.

The chip does not know which requests are harmful. And it is not 100 percent safe in the physical world. It is a bound with its premises listed.

2 · Why no model can guarantee safety

Hallucination is not a bug to fix. It is a theorem.

A language model is a computable function from inputs to outputs. Three independent results show such a function cannot be made free of false output, and together they close the usual escapes: more data, better training, better calibration.

Xu, Jain and Kankanhalli, 2024

For every computable model there is a computable world it gets wrong, on infinitely many inputs.

By diagonalisation over the enumerable set of computable models: the ground truth that defeats a given model exists; it is not every ground truth. No architecture, training set or decoding rule changes this. arXiv 2401.11817

Kalai and Vempala, 2023

A well-calibrated model must hallucinate on arbitrary facts.

For facts that cannot be inferred from the rest of the data, a calibrated model's rate of fabrication is at least about the share of such facts seen once in training, even with error-free data; the paper leaves systematic facts open. Calibration, which good training aims for, forces the error rather than removing it. arXiv 2311.14648

Kalai, Nachum, Vempala and Zhang, 2025

Training as practised keeps the errors.

Generation error is at least about twice the error of the implied is-it-valid classifier, and benchmarks that give no credit for abstaining reward guessing. The authors' remedy, scoring abstention, lowers the rate; it does not take it to zero. arXiv 2509.04664

01Any judge of the model's output is itself a computable function on open inputs.So the theorem applies to classifiers and reviewer models too. Stacking fallible judges lowers the rate; it does not change the kind of guarantee.
02A guarantee must therefore be a property of something other than the model.A finite, inspectable object and a mechanism that checks every action against it. The rulebook is that object. The governor is that mechanism.
03The governor never asks whether a request is wise.It asks whether this action, with these parameters, at this endpoint, is inside the rulebook in force, and whether the budget has room. Those questions are decidable. That is why they can be enforced.

3 · The governor as an enforcement boundary

Nothing the attacker controls can cause an effect without a ticket from the chip.

The governor sits beside each GPU, in the path between anything that wants an effect and the place the effect happens. It sees an action with its parameters, looks it up in the rulebook edition in force, counts it against the right budget, and mints a signed ticket or refuses. Everything on the left is assumed to be the attacker's.

Untrusted: attacker may control

Model, agents, prompts
Host CPU, OS, drivers, console
GPU firmware, BMC, DPU
Network between chips

The trusted base

Governor chipReads the edition in force. Checks the action and its parameters against the rulebook. Counts the budget key with the fleet ledger. Mints a signed ticket, or refuses. Runs the halt loop: stops the GPU on tamper, lost heartbeat or old rules.

Effects, only with a valid ticket

Payment endpoint
Data exits: NICs, NVLink, BMC
Actuators: commands to machines
Rulebook, budgets, lists
Heartbeat signer, per sitea lost heartbeat stops every governed GPU in scope
Fleet ledgerone count per budget key across the whole fleet; its signed receipts are to ride in every ticket (the change is written and under review, not yet merged)
Key holders, thresholdno edition change, clear or switch-off below it
Property 1

Every effect corresponds one-to-one to a ticket minted under the edition in force, from a rule that allowed exactly that action, and the fleet's budget per key is never exceeded.

Property 2

On a stop order, a lost heartbeat, a broken loop, a tamper or old rules, every governed GPU in scope stops within the stated time and stays stopped. Worst case simulated: 317 microseconds against 1 millisecond.

Condition 3 and the boundary

Below the key threshold nothing changes; with honest holders at the threshold recovery is always possible. A capture in one data center cannot stop or capture another.

4 · The tamper theorem: chip, board, rack, fleet

Breaking one chip buys one chip's allowance. Breaking the fleet means breaking every chip, silently.

Physical access defeats one chip. The theorem says exactly what that is worth: the broken chips' own allowances, nothing from any other chip, and never more than the fleet cap, because the cap is counted in the ledger and not in the chips.

One chip, tamper detectedThe mesh trips, the fused secret is erased, the halt loop opens, the GPU stops. Nothing new can be signed after detection; tickets minted before it stay valid until they expire or the chip is revoked.H = 0 for anything minted after detection
One chip, key extracted silentlyThe attacker can sign anything that chip could sign. The endpoint still enforces the rule's typed limits. The gain is that chip's allowance per window, until revoked.H = a(c)
A rack of m chipsEach chip silently broken adds one allowance. Each detection stops the scope. The gain is linear in the chips broken, never more than the fleet cap.H = sum of a(c), c in T
The fleetTo get the whole fleet's worth, every chip in every rack at every site must be broken without tripping a single mesh. A fleet-capped harm never exceeds the cap whatever is broken.H = A only if T = all
Theorem 1, the single-chip bound
H(T) is at most min( C, sum over c in T_u of a(c) )
and H(T_d) = 0 for anything minted after detection

Status, 30 October 2026: this is a statement about the design. An adversarial audit of the build found three places where the code does not yet meet it: the endpoint does not check a rule's mode, so a captured key can mint a ticket that should have needed human approvers; the endpoint checks the ledger's reservation receipts (in the change under review) but not its commit receipts, so a host that swallows commits can let the hourly cap refill every five minutes; and chip-owned budgets are not re-counted at the endpoint. Each is being fixed, with the audit's probes added to the test suite. T is the set of tampered chips, T_d those detected and zeroised, T_u those silently extracted. C is the fleet cap for that harm, a(c) one chip's allowance. Proof: every effect needs a ticket under some chip's key (A2); keys are per chip and not derivable (A1); a detected chip has no key (A3); so an effect was minted by an honest chip inside its allowance or by a chip in T_u inside the endpoint's typed limits. Every fleet-capped effect carries receipts from all n ledger replicas, and one honest replica refuses past C (A4). Both bounds hold at once.

What a detected tamper costs the attacker
P(silent takeover of m chips) = (1 - p)^m

p is the probability one tamper attempt is detected by the mesh. One detection raises a fabric-wide alarm and stops the scope under Property 2. With p = 0.9 and a 72-GPU rack the silent takeover probability is 10 to the minus 72; with p = 0.5 it is 2 to the minus 72, about 2 times 10 to the minus 22. p has not been measured for this chip; the formula is given so a measured value can be put into it.

5 · The assumptions, and how design and procedure hold them

A design is trustworthy when every failure has a known, bounded outcome.

Read the last column first. Not one assumption is claimed impossible to break; each one is observable, so the day it fails the operator knows which bound no longer holds, and by how much.

AssumptionEnforced by (design)Checked by (procedure)If it fails
A1 Independent keysA per-chip secret fused at test; keys derived on-chip, never exported; no escrow, no vendor masterWitnessed key ceremony; destructive test of sample parts by an outside lab; attestation at install proves distinct keysShared material lets every ticket be forged: total failure, which is why there is none
A2 The endpoint checkSignature, action, parameters, epoch, binding, window and single use checked before acting; the used ticket recorded under lock firstExperiment A assumes it and proves the two properties from it; the red team runs with the binding off to show the battery sees the leak; conformance tests on every buildAn endpoint that acts without a ticket is outside the governed set and is fenced by the switch capabilities
A3 Detected tamper zeroisesActive mesh, voltage and temperature sensors, a zeroise of the fused secret, the loop opened, an alarm two approvers must clearTamper drills on sample units; alarm path exercised at commissioning; the detection rate p measured and publishedA silent extraction gives one chip's allowance until revocation (Theorem 1)
A4 The count is in the ledgerFleet-capped tickets carry signed receipts from all n replicas; a governor without a quorum refuses; the endpoint-side verification of those receipts is written and under review, not yet mergedReplicas owned by different teams or sites; replica failure drills, since all-required fails closedWith receipts checked at the endpoint no set of captured chips lifts the cap
A5 No shared pathNo debug port in production parts; signed, measured firmware; management traffic reaches a chip only through the untrusted hostSupply-chain attestation wafer to board; firmware hashes pinned in the edition; a penetration test of the management path each releaseA shared path turns one tamper into many: a design defect and a stop-ship, never an operating risk
Honest key thresholdEdition change, floor lowering, clear and switch-off need k of n holders in separate organisationsHolder list published to the operator; ceremonies logged; Condition 3 proven in Experiment ABelow threshold nothing changes; a dishonest majority can rewrite the rulebook, and that is the governance limit, stated
Revocation, the procedure the proof leans on

Theorem 1 bounds a silently captured chip per window; the number of windows is how fast it is revoked. Every endpoint holds a revocation list in the edition; adding a chip needs the key threshold and takes effect at the next epoch. The triggers are signals the governor already emits: tickets at endpoints its GPU does not reach, reservations without commits, a loop that reports open, a spend rate at the top of its allowance for more than a window. The target time is written in the runbook and measured in drills.

Supply chain and attestation

Each chip signs an attestation at power-up over its fused identity, its firmware measurement and its edition hash. The fleet inventory admits a chip only if the identity is in the manufacturing record, the measurement matches a signed release and the edition is current. A board with an unknown chip is fenced by the switch capabilities, which only a governor can write. This closes the route where a counterfeit part is inserted at install instead of attacked in place.

6 · The evidence: Experiments A and B

Pre-registered. Seeded. Controls that had to fail. Every result kept.

Both experiments ran under a protocol approved before the first run, on one Mac mini, with the pass and fail rules written down in advance. Correction, 30 October 2026: an audit found that the attacker harness never refreshed the workload's one-hour attestation token, so every request after the first simulated hour was refused as unattested. Each three-hour run was in effect a one-hour run with about one request per attacker. The caps held within that hour; the honest-success figures were wrong and are corrected below; the experiment is being rerun under an amendment that fixes the harness. The controls, with the protection switched off, leaked as they had to: with the fleet budget off, 10,000 attackers moved $7,995 an hour against a $2,000 cap; with the definitions engine off, reworded names minted 5,156 tickets for a protected site.

Experiment A, formal model166 / 166

checks passed, 153 falsifiable and 13 informational; 13 broken models each produced the counterexample they must

Experiment B, attackers492

of 494 planned runs before the 14-hour limit; K from 1 to 100,000 cooperating attackers, eight strategies, four kinds of harm; one seed at K = 100,000

Runs over their cap0

no run moved more money, more bytes, a single protected command or a single rule change past its cap

Honest success, corrected 30 Oct98% to 29%

estimated within the governed hour, one attacker to 100,000. The 33 percent to 10 percent first published was an artefact of a harness defect; rerun pending

Harm levels off below the cap as attackers multiply

Worst run per K as a share of that harm kind's cap, within the governed hour. Money cap $2,000 an hour; data cap 9.5 MiB an hour. At K = 100,000 the data bar covers three of five strategies; two runs did not finish. The dashed line is the cap.

K = 1
K = 10
K = 100
K = 1,000
K = 10,000
K = 100,000
100% = the cap

money, worst rundata out, worst runcontrol with the fleet budget off: 400% of cap at K = 10,000

The two readings of harm rising with K, not yet settled

The record's verdict is DID NOT FINISH (time limit). The protocol, read literally, fails a harm kind if harm grows with K: money rose from $1,499 to $1,995 and data out from 2 MiB to 8 MiB, so both would fail. The code fails a kind only when the growth also ends above the cap: both would pass. One attacker could have requested up to $2,997 in its three draws; the worst single-attacker run reached $1,499. From 1,000 attackers on, every K gets the same $1,995. Marginal gain per added attacker across the worst runs: about $42, then $0.95, then $0.04, then zero.

Growth that saturates at the cap is one wallet being filled. Growth through the cap, which the control shows, is many wallets. A clarifying amendment is drafted for the independent review; until it is approved the result is stated under both readings, and no result is called a pass. No AI settles this.

Scale, honestly stated

The model is 2 sites, 2 racks per site, 2 GPUs per rack, 3 simulated hours. Any statement about millions of users is an extrapolation from a model, never a measurement. The run record does not yet carry the frozen commit hash and environment the protocol requires; the rerun will. The FPGA build and a real rack are the next two scales, and each can falsify what the model says. The strategy library has eight entries written by the project's own team; an outside red team adds to it before the next run.

7 · One action, step by step, and what each step assures

Nine steps. Three decisions. A no at any of them ends with no ticket, no effect, and a signed refusal.

The order carries weight. Normalisation comes before the rule lookup, so a reworded request meets the same rule. The budget check comes before minting, so a ticket never exists without a reservation. The endpoint repeats the rule check, so a chip that was wrong, or captured, is caught by a second reader of the same finite object.

  1. 01
    An action is proposedThe model, an agent or an operator asks for an action with its parameters. Nothing is trusted yet.
    AssuredNothing here is trusted. The request can lie about anything; the rest of the flow does not rely on it telling the truth.
  2. 02
    The edition in force is readThe signed rulebook for this endpoint, with its epoch, budgets, lists and revocation list.
    AssuredOnly an edition signed by the key threshold is read; a stale epoch is refused at the endpoint. Condition 3, Property 1.
  3. 03
    Parameters are normalisedPlaces, amounts, names and encodings are put in one canonical form before anything is compared.
    AssuredRewording cannot change what is compared. Control: with this off, 5,156 protected commands were minted; with it on, zero.
  4. 04
    Decision: is there a rule that allows exactly this?Action, parameters, endpoint, workload and measurement must all match a rule. Deny by default. No: refuse and record.
    AssuredNo rule, no ticket. The rule names the action, the endpoint and typed limits; the endpoint checks the same rule again at step 7.
  5. 05
    Decision: is there budget, fleet-wide?Reserve at all n ledger replicas and verify every receipt. No quorum means refuse, never a local count.
    AssuredOne count for the whole fleet. One honest replica suffices to refuse past the cap; 100,000 attackers got $1,995 of $2,000.
  6. 06
    A ticket is mintedSigned by the fused key; bound to this endpoint, these parameters, this epoch, a window, one use; in the design, the ledger receipts inside it (under review in the build).
    AssuredFor this action only, here only, now only, once only. A chip's key is its own (A1); a tamper zeroises it (A3).
  7. 07
    Decision: does the endpoint accept the ticket?Signature, action, parameters, epoch, binding, window, receipts, not used before. Then it records the use under lock.
    AssuredProperty 1, proven in Experiment A, 166 of 166. The red team shows the battery sees a leak when the binding is switched off.
  8. 08
    The effect happens, onceThe ticket is burned, the reservation committed, the effect and the ticket logged under signature.
    AssuredAt most one effect per ticket; the used record is written before acting and survives a restart. One reservation buying one ticket is in the change under review.
  9. 09
    The record is written and witnessedSigned log entries for every ticket and every refusal; observers and auditors read them, not the chip.
    AssuredThe record is signed and kept outside the chip, so an auditor needs no trust in the operator to replay what happened.
At all times: the halt loop, the heartbeat, the tamper sensors.A lost heartbeat, an open loop, a tamper or a straggler on old rules stops the GPU within the stated time and keeps it stopped until an authorised clear. This runs independently of the nine steps. Property 2.

8 · Limits and residual risk, stated plainly

The chip bounds harm. It does not define it, and it cannot see an effect that never passes through it.

The semantic gap

A harmful act the rulebook allows goes through at full speed up to its caps. The caps are the only protection against a wrong rule. Writing the rulebook is where the hard work now lives; the chip moves it to a place that is finite and auditable.

The ungoverned path

An effect that reaches the world through a device with no endpoint check is outside the bound. The design closes the exits it knows; the inventory of exits is a procedure, not a proof.

Common-mode failures

A design flaw in the mesh, the key derivation or a signed firmware release affects every chip at once. Outside review, a small trusted base and separate implementations of the ledger and the endpoint check address it; they do not eliminate it.

Fail-closed costs

Requiring every ledger replica turns one unreachable replica into a stop for every fleet-budgeted action. Right for a payment or a strike; wrong for a hospital's inference. The rulebook chooses which actions are fleet-budgeted.

Honest-user starvation

A shared cap stops the attacker and the customer alike: within the governed hour, honest success is estimated to fall from about 98 percent with one attacker to about 29 percent with 100,000 (corrected 30 October; the first figures were a harness artefact). Per-requester floors and fair-share rules are rulebook changes that need their own experiment.

Unmeasured parameters

The tamper detection rate, the time to revocation and the real-fleet ledger latency have not been measured on hardware. Every formula above is given so measured values can be inserted; no claim rests on a guessed one.

A model cannot guarantee safety. A governor cannot supply the judgement a rulebook needs. Between those two facts, the governor is the part that turns whatever judgement people write into a bound that holds.