← All projectsGitHub
Verification games & slashing

Can stake shorten a challenge window when proposers can be bribed?

research/challenge-window

Optimistic-verification challenge windows with bribable proposers: exact gamble-then-bribe attacker recursion, closed-form window, stake cannot shorten it under an exogenous bribe price (63 blocks for S=10…1600), bounty-funded priority fees give S·w ≈ G/((1−ρ)θ).

9 tests

What it found

In optimistic verification a fraud pays G unless a challenge is included within w blocks; the attacker controls each proposer w.p. ρ and otherwise pays b to censor. The exact attacker recursion V(n) = ρV(n−1) + (1−ρ)max(−S, V(n−1)−b) gives a closed-form deterrence window (0 mismatches in 5000 instances; Monte Carlo agrees) with a gamble-first, bribe-last optimal attack. A luck-only analysis underestimates the window 100–170×; with an exogenous bribe price the window is 63 blocks for every stake from 10 to 1600; if the bounty is paid as a priority fee the price becomes θS and S·w ≈ G/((1−ρ)θ). Stylised.

A figure from its own output

Figure produced by research/challenge-window: window_vs_stake
challenge-window/experiments/window_vs_stake.svg, written by the project's own experiment code.

Paper, code and results

More in Verification games & slashing

All 19 Verification games & slashing projects →

Other research topics

Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & human sciences1

Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.