Register 05 · Game theory

Zero-Sum.

Zero-Sum is a strategic-interaction primitive: the game shape Planisphere can detect inside an AI tool deployment's behaviour.

Open the Console See how a record is checked

register 05 · Game theory· reference mark

01 ·

Promise. strategy

The contract this mark binds — derived, not asserted.

Zero-Sum is a strategic-interaction primitive: the game shape Planisphere can detect inside an AI tool deployment's behaviour.

Answers: How does Planisphere recognise a Zero-Sum pattern in an AI tool deployment?

02 ·

What this is.

Twelve marks · strategic interaction primitives · same construction

Use. strict conflict · Σ = 0.

Source. opposed arrows + brass equality bars.

Register. 05 · Game theory — one of the 17 registers of the PLANiSPHERE corpus library.

03 ·

See it work.

Evidence record you can check — not code you have to trust.

Planisphere measures your tool deployment against Zero-Sum and seals the result into a signed, Merkle-rooted evidence record. The grade recomputes on your own hardware; the model state never crosses the boundary.

See the evidence spine →See how a record is checked

04 ·

The board that carries this.

Related marks, and the surface this one funnels to.

Zero-Sum is a reference mark in the Game theory register. Read the related buyer-facing product context at /evidence.

Auction reg 05 · mechanism · bid clearing Coalition reg 05 · winning subset · Shapley value Cooperative reg 05 · surplus sharing · core solution Extensive Form reg 05 · game tree · sequential moves

05 ·

Routes here from.

Where this mark is referenced in the Planisphere surface.

Methodology

Any internal link in the Planisphere site that names "Zero-Sum" canonicalises here.

06 ·

Sibling marks. Game theory

Same register · same construction.

normal form · 2×2 game

grid + diagonals + brass equilibrium cell

Nash Equilibrium

best-response fixed point

2 best-response curves + brass intersection

game tree · sequential moves

root + branches + brass optimal path

probability distribution over actions

5 bars + brass mode + dashed curve

surplus sharing · core solution

2 player circles + brass shared zone

Prisoner's Dilemma

dominant defection · (D,D)

2×2 C/D grid + brass equilibrium cell

saddle point · worst-case bound

surface + brass ridge + valley + saddle

winning subset · Shapley value

3 player circles + brass enclosing curve + outsider

iterated play · folk theorem

4 round nodes + brass cycle arrow + n→∞ dots

mechanism · bid clearing

gavel + handle + brass sound block + impact

asymmetric info · costly type reveal

brass sender + receiver + envelope + noise curves

See the record Zero-Sum asks for.

The console shows the evidence; the docs show the endpoints; the briefing shows what the product does and does not claim.

Open the Console Read the Docs Read the capability briefing

API ·

When a regulator asks for proof, hand over records — not assurances.

record the duty · seal the receipt · verify offline

Planisphere records each duty event — an output marked, a disclosure shown, a review made — and seals it into a receipt that verifies offline against our published keys. You send hashes, never content. A record is evidence a third party can check; it is not a certification and not a legal determination.

Open the Console Read the Docs Read the capability briefing

See how a record is checked