✗ Failed on benchmark 2026

Koopman Deadline Controller

Implementation & benchmark of arXiv:2608.05956 — Certifying Collective Reasoning in Multi-Agent Systems via Koopman Spectral Analysis

Usefulness8/10
Difficulty5/10
Novelty7/10

Source paper: Certifying Collective Reasoning in Multi-Agent Systems via Koopman Spectral Analysis arXiv:2608.05956 ⓘ · analyzed Aug 31, 2026

AI-generated research hypothesis, automatically tested. Not peer-reviewed.

Idea description

Learn a low-dimensional Koopman operator from successive states of an iterative neural system, such as debate agents, recurrent refinement blocks, or diffusion denoising trajectories. Use the magnitude of the subdominant eigenvalue to predict the remaining number of rounds required for disagreement to fall below a target tolerance, and stop computation when the predicted deadline is reached rather than using a fixed round budget.

Formulas

$$z(t+1)=F(z(t))$$
$$(\mathcal{K}\psi)(z)=\psi(F(z)),\qquad (\mathcal{K}\psi)(z)=\mathbb{E}[\psi(F(z))]\ \text{for stochastic dynamics}$$
$$\widehat K=YX^{\dagger},\qquad X=[\phi(z_1),\ldots,\phi(z_M)],\quad Y=[\phi(z'_1),\ldots,\phi(z'_M)]$$
$$r_{\varepsilon}=\left\lceil\frac{\log(\varepsilon/D_t)}{\log|\lambda_2|}\right\rceil,\qquad 0<|\lambda_2|<1$$

Mathematical statement

The paper defines a discrete dynamical system by $z(t+1)=F(z(t))$, where $z(t)\in\mathbb{R}^{n}$ is the complete multi-agent state and $F$ is one round of nonlinear computation. For any scalar observable $\psi:\mathbb{R}^{n}\to\mathbb{R}$, the Koopman operator is $(\mathcal{K}\psi)(z)=\psi(F(z))$ for deterministic dynamics and $(\mathcal{K}\psi)(z)=\mathbb{E}[\psi(F(z))]$ for stochastic dynamics. Although $F$ may be nonlinear, $\mathcal{K}$ is linear. In an implementation, choose a dictionary of $d$ observables $\phi(z)=[\phi_{1}(z),\ldots,\phi_{d}(z)]^{\mathsf T}$, collect $M$ transitions $z_m\mapsto z'_m$, and estimate a finite Koopman matrix $\widehat K$ by least squares: $X=[\phi(z_1),\ldots,\phi(z_M)]$, $Y=[\phi(z'_1),\ldots,\phi(z'_M)]$, and $\widehat K=YX^{\dagger}$. Sort eigenvalues by magnitude as $|\lambda_1|\ge |\lambda_2|\ge\cdots$; after removing the invariant consensus mode $\lambda_1\approx1$, the disagreement mode contracts approximately as $|\lambda_2|^r$. For target residual $\varepsilon$ and current disagreement $D_t$, predict $r_{\varepsilon}=\left\lceil\log(\varepsilon/D_t)/\log|\lambda_2|\right\rceil$ when $0<|\lambda_2|<1$.

Implementation notes

Integrate this at the controller around an iterative neural computation, not inside the base model initially. The first target should be a small multi-agent QA system or a recurrent transformer refinement loop in which each round produces agent belief embeddings $h_i^t$ and a final answer distribution. At each round form $z_t=[h_1^t;\ldots;h_N^t]$, and compute a fixed observable vector $\phi(z_t)$ containing the flattened mean embedding, pairwise disagreement statistics, answer logits, and squared versions of the first few PCA coordinates. Maintain a rolling buffer of transitions $(\phi(z_t),\phi(z_{t+1}))$. Once the buffer contains $M\ge 2d$ samples, compute the ridge-stabilized estimator $\widehat K=YX^{\mathsf T}(XX^{\mathsf T}+\alpha I)^{-1}$, where $\alpha$ is a small numerical regularizer. Compute the eigenvalues of $\widehat K$, identify the eigenvalue closest to one as the consensus mode, and set $|\lambda_2|$ to the largest remaining magnitude after rejecting modes with poor one-step prediction residual. Let $D_t$ be the norm of the disagreement observables relative to their consensus projection. Estimate the remaining rounds using the displayed logarithmic formula, clip it to a safe range, and stop early only when both the predicted residual is below $\varepsilon$ and the actual answer distribution changes by less than $\delta$ for two consecutive rounds. The paper supplies the Koopman construction and spectral certificate; the engineer must estimate $K$, eigenvalue uncertainty, and residuals empirically. Begin with 8 agents and 4 maximum rounds on GSM8K or a synthetic consensus task, comparing fixed-round debate and confidence-threshold stopping at equal answer accuracy. Success is lower mean rounds and FLOPs with no accuracy loss, while failure is systematic premature stopping, unstable eigenvalues, or worse calibration.

Verification

Failed on benchmark

Stage 1 · Toy mechanism gate: Passed ✓

Stage 2 · Mechanism transferred to benchmark: Not reproduced ✗

Stage 2 · Practical benchmark result: Inconclusive

Methodology: 8 paired seeds, permutation test (p<0.05) against a learning-rate-tuned baseline. How verification works

Stage 1 — Mechanism check agent confidence 8/10

Built a runnable Koopman deadline-controller MVP for an 8-agent consensus dynamical system with ridge Koopman estimation and conservative stopping. The mechanism manifested clearly: estimated subdominant eigenvalues matched true contraction rates within 1.95e-7, geometric residual ratios matched theory, and all logarithmic deadline predictions matched analytic deadlines. The controller achieved a modest reduction from 12 to 10 rounds for contraction rates 0.5 and 0.7, but warm-up and the two-round stability gate limited savings; this is a toy-mechanism win, not evidence of a neural QA speedup.

Agent confidence
8/10
Baseline
Fixed 12 rounds for all tested contraction rates.
Idea
Mean rounds over 20 runs: 10.0 at rho=0.5, 10.0 at rho=0.7, 11.7 at rho=0.8, and 12.0 at rho=0.9. Maximum Koopman eigenvalue estimation error was 1.95e-7; deadline prediction error was zero for all tested tolerances.

Limitations: Only a deterministic synthetic consensus system was tested. No neural recurrent/debate model, GSM8K accuracy, FLOP measurement, stochastic dynamics, noisy eigenvalue uncertainty, calibration, or larger-scale controller overhead study was performed.

How to run: python3 koopman_deadline.py

Stage 2 — Benchmark vs. tuned baseline (arXiv:2608.05956)

Ahead of the baseline (−6.1%) but not statistically significant (p=0.8002, wins 5 / 8 paired seeds).

Benchmark
Dynamics forecasting
Model
rnn_small
Paired seeds
8
Baseline mean
0.0344
Idea mean
0.0323
Effect (Δ)
-0.0021 (−6.1%; negative = idea better)
Wins
5 / 8 paired seeds
p-value
0.8002 (permutation test, 20 000 shuffles)
Smallest detectable effect
±59.0%
Mechanism
Not confirmed ✗
Practical effect
Inconclusive
Baseline tuning
swept over 0 configs
Limitations:

Only the built-in dynamics pendulum track was tested with 400 training samples, 400 test samples, 8 epochs, and a four-round horizon. No larger recurrent/debate model, variable maximum-round budget, FLOP or wall-clock profiling, noisy Koopman-buffer robustness study, or broader accuracy-preserving early-stop analysis was performed.

How to run: python3 koopman_bench.py

Verdict computed by deterministic test code from paired-seed statistics — not by the language model.

Stage 2 — Benchmark latest Failed ✗

Agent confidence: 9/10

Implemented the Koopman deadline controller around the structurally matched dynamics track using freshly trained identical rnn_small systems, paired seeds, baseline sweep, shared hyperparameter grid, and NN-measured mechanism diagnostics. The idea had a small lower-MSE mean improvement (-0.002105) but was not significant (permutation p=0.80015), and the predicted contraction ratio 0.295 differed substantially from the observed ratio 1.008, so the mechanism was not confirmed quantitatively.

Baseline
Best lr=0.003; 8-seed test MSE 0.0343647.
Idea
Best lr=0.01; 8-seed test MSE 0.0322596; paired delta=-0.0021050; 5/8 wins; permutation p=0.80015; mean rounds 4.0.

Benchmark result

Ahead of the baseline (−6.1%) but not statistically significant (p=0.8002, wins 5 / 8 paired seeds).

Benchmark
Dynamics forecasting
Model
rnn_small
Paired seeds
8
Baseline mean
0.0344
Idea mean
0.0323
Effect (Δ)
-0.0021 (−6.1%; negative = idea better)
Wins
5 / 8 paired seeds
p-value
0.8002 (permutation test, 20 000 shuffles)
Smallest detectable effect
±59.0%
Mechanism
Not confirmed ✗
Practical effect
Inconclusive
Baseline tuning
swept over 0 configs
Limitations:

Only the built-in dynamics pendulum track was tested with 400 training samples, 400 test samples, 8 epochs, and a four-round horizon. No larger recurrent/debate model, variable maximum-round budget, FLOP or wall-clock profiling, noisy Koopman-buffer robustness study, or broader accuracy-preserving early-stop analysis was performed.

How to run: python3 koopman_bench.py

Artifacts

Implementation overview ⬇ Download all as ZIP 6 files · code, reports and structured results