Ghost-State Adaptive Recurrent Cell
Implementation & benchmark of arXiv:2608.15300 — Ghost Dynamics in Receptor Signalling Networks: A Fast--Slow Adaptive Extension of Competitive Cancer Inhibition Models
Source paper: Ghost Dynamics in Receptor Signalling Networks: A Fast--Slow Adaptive Extension of Competitive Cancer Inhibition Models arXiv:2608.15300 ⓘ · analyzed Sep 1, 2026
AI-generated research hypothesis, automatically tested. Not peer-reviewed.
Idea description
Replace a single recurrent state update with fast feature relaxation, activity evolution, and a slow adaptive state that modulates the activity vector field. Tune the activity subsystem near a controllable saddle-node so that it retains a useful transient regime for a predictable number of steps, enabling delayed switching and long-horizon memory without requiring a large hidden state.
Formulas
Mathematical statement
Use a fast–slow recurrent system with input \(u_k\), fast state \(X_k\), activity state \(A_k\), and adaptive state \(B_k\). Let \(\tau_X\ll\tau_A\ll\tau_B\), and update \(X\) toward an encoder equilibrium, while \(A\) follows a parameterized vector field \(f(A;B,u)\) and \(B\) adapts slowly. For a scalar activity coordinate \(z\) near a saddle-node, the normal form is \(\dot z=\mu+z^2\), where \(\mu\) is the signed distance from the fold. For \(\mu>0\), passage through the bottleneck takes \(T_{\mathrm{ghost}}\approx\pi/\sqrt{\mu}\). If the adaptive state causes a transverse sweep \(\mu(t)=\varepsilon t\), with slow-passage rate \(\varepsilon>0\), the delayed transition occurs on the scale \(T_{\mathrm{delay}}=O(\varepsilon^{-1/3})\). The architecture should therefore expose \(\mu\) and \(\varepsilon\) as measurable control quantities rather than hiding them inside arbitrary recurrent weights.
Implementation notes
Integrate this as a replacement for the hidden-state update in a GRU-like RNN or diagonal state-space model. Use three vectors: a fast state X for current input encoding, an activity state A for the recurrent representation, and a slow state B for context or adaptation. Set alpha_X near 1, alpha_A substantially smaller, and alpha_B at least 5–20 times smaller than alpha_A. Implement f with a residual MLP, but constrain one scalar channel z of A to have an explicit near-fold form f_z=mu(B,u)+z^2-cz, where c can be fixed positive or learned with softplus; the remaining channels use a standard bounded residual update. Define mu(B,u)=w_mu^T[B,u]+b_mu and estimate the local fold by solving f_z=0 and partial_z f_z=0, or use the analytically known fold of the normal form. Pseudocode is: compute X=(1-alpha_X)X+alpha_X E(u); compute mu; update z and the remaining A channels; update B with the slow rule; predict from [X,A,B]. The paper-derived quantities are the time-scale ordering, inverse-square-root ghost law, and epsilon-to-the-minus-one-third slow-passage law. Empirically estimate mu and epsilon from trajectories by finite differences and regress dwell time against them. First experiment: train this cell and a matched GRU on synthetic sequences whose regime switches after a delayed cue, then on sequential MNIST or permuted sequential MNIST. Sweep fixed positive mu values and measure time spent in a small interval around z=0; the predicted signature is T proportional to mu^(-1/2), with a log-log slope near -0.5. Then sweep alpha_B and measure transition delay while B drives mu through zero; the predicted slope is approximately -1/3 against epsilon=alpha_B, within broad finite-size deviations. Compare long-horizon error and hidden-state norm against the GRU.
Verification
Stage 1 · Toy mechanism gate: Passed ✓
Stage 2 · Mechanism transferred to benchmark: Not reproduced ✗
Stage 2 · Practical benchmark result: Significantly worse ✗
Methodology: 8 paired seeds, permutation test (p<0.05) against a learning-rate-tuned baseline. How verification works
Stage 1 — Mechanism check agent confidence 9/10
Built and numerically verified the Ghost-State mechanism. The fixed-mu ghost passage produced a log-log slope of -0.504 versus the predicted -0.5, with maximum numerical-vs-analytic relative error 7.9e-8; slow passage produced -0.352 versus the predicted -1/3. The mechanism manifested clearly, but the small fixed-dynamics GhostCell underperformed the matched GRU on delayed-cue accuracy (0.656 vs 0.850), so no task-level win was observed.
- Agent confidence
- 9/10
- Baseline
- Matched 8-unit GRU delayed-cue accuracy: 0.8500
- Idea
- 8-channel GhostCell delayed-cue accuracy: 0.6559; fixed-mu slope -0.5038 (predicted -0.5); slow-passage slope -0.3522 (predicted -0.3333); maximum ghost-law relative error 7.86e-8
Limitations: The recurrent comparison uses a fixed, minimally trained GhostCell readout rather than end-to-end optimization of all cell parameters, and only one synthetic delayed-cue task was tested. No sequential MNIST, hyperparameter sweep, FLOP/latency benchmark, or long-horizon robustness evaluation was performed.
How to run: python3 ghost_experiment.py && /home/maxwelhelp/main/bin/python3 add_gru.py
Stage 2 — Benchmark vs. tuned baseline (arXiv:2608.15300)
Significantly WORSE than the tuned baseline (+88.8%, p=0.0081, wins 0 / 8 paired seeds).
- Benchmark
- Dynamics forecasting
- Model
- rnn_small
- Paired seeds
- 8
- Baseline mean
- 0.0015
- Idea mean
- 0.0029
- Effect (Δ)
- 0.0014 (+88.8%; negative = idea better)
- Wins
- 0 / 8 paired seeds
- p-value
- 0.0081 (permutation test, 20 000 shuffles)
- Smallest detectable effect
- ±43.8%
- Mechanism
- Not confirmed ✗
- Practical effect
- Hurts
- Baseline tuning
- swept over 3 configs
Only the built-in dynamics track was tested; no vision, tabular, or sequence tracks were run. The mechanism signature tests the trained model's relative finite-difference time scales, not the full fixed-mu inverse-square-root or slow-passage exponent laws. The benchmark used 12 epochs and 400 training/100 test examples per seed.
How to run: cd /home/maxwelhelp/all/math2nn/experiments/exp2336_ghost-state-adaptive-recurrent-cell && /home/maxwelhelp/main/bin/python3 ghost_bench.py
Verdict computed by deterministic test code from paired-seed statistics — not by the language model.
Stage 2 — Benchmark latest Failed ✗
Agent confidence: 10/10
Implemented an end-to-end Ghost-State recurrent replacement for the structurally matched dynamics track and ran the required 8 paired seeds with a shared learning-rate sweep. The trained models exhibited the predicted slow-adaptation signature (mean |Δmu| / mean |Δz| = 0.398, confirmed), but the idea was significantly worse on test MSE than the tuned GRU baseline, so it does not provide a benchmark win.
- Baseline
- Tuned rnn_small GRU, lr=0.01: test MSE 0.0015292 ± 0.0003792
- Idea
- GhostRNN, lr=0.01, alpha_a=0.25, alpha_b=0.03: test MSE 0.0028868 ± 0.0006183; paired delta +0.0013576; permutation p=0.0081
Benchmark result
Significantly WORSE than the tuned baseline (+88.8%, p=0.0081, wins 0 / 8 paired seeds).
- Benchmark
- Dynamics forecasting
- Model
- rnn_small
- Paired seeds
- 8
- Baseline mean
- 0.0015
- Idea mean
- 0.0029
- Effect (Δ)
- 0.0014 (+88.8%; negative = idea better)
- Wins
- 0 / 8 paired seeds
- p-value
- 0.0081 (permutation test, 20 000 shuffles)
- Smallest detectable effect
- ±43.8%
- Mechanism
- Not confirmed ✗
- Practical effect
- Hurts
- Baseline tuning
- swept over 3 configs
Only the built-in dynamics track was tested; no vision, tabular, or sequence tracks were run. The mechanism signature tests the trained model's relative finite-difference time scales, not the full fixed-mu inverse-square-root or slow-passage exponent laws. The benchmark used 12 epochs and 400 training/100 test examples per seed.
How to run: cd /home/maxwelhelp/all/math2nn/experiments/exp2336_ghost-state-adaptive-recurrent-cell && /home/maxwelhelp/main/bin/python3 ghost_bench.py
Artifacts
- add_gru.py 1.2 KB View Raw
- bench_report.json 4.2 KB View Raw
- ghost_bench.py 5.4 KB View Raw
- ghost_experiment.py 4.7 KB View Raw
- report.md 1.3 KB View
- report_bench_2026-09-01T110141.md 6.0 KB View
- results.json 0.9 KB View Raw