Fiber Fingerprints of Hidden Learning-State Dynamics
Abstract
A learning system can occupy execution states that are indistinguishable under every declared present-behavior readout yet respond differently to future training. We formalize this through fiber fingerprints: controlled future-learning response laws restricted to present-behavior equivalence classes. Prefix-compatible finite probes induce a predictive quotient functor, a Nerode-type minimal recursively sufficient representation, and a canonical set-level predictive fiber without assuming smoothness, reversibility, finite rank, or a manifold. Under an explicit finite-dimensional Hilbert realization, response decomposes into visible, visible-mode-reuse, and irreducible-new sectors; a history-reachability bridge retains only distinctions generated by natural training histories. Conditional mechanism results then identify a graph-Hodge chronology decomposition, a regular switching class with root-mean-square scale and finite-scale corrections, and an exact Adam moment section whose immediate adaptive field is constant while common future gradients can reveal hidden moment differences. Frozen Transformer--LoRA--AdamW studies with Qwen2.5-7B and Mistral-7B-v0.3 support a local action backbone, longer-horizon first-return non-closure, and fresh visible-relative completion with output-range reuse and a low-rank irreducible sector. Stronger claims remain bounded by preregistered negative or mixed results: re-anchored transport is unresolved above its measurement floor; the strict finite-grid Hodge-- conjunction is unmet despite prospective contraction; Qwen accessibility is not established in the frozen raw moment chart; and Mistral revelation is future-context dependent rather than bank invariant. Within these support-, scale-, metric-, and context-resolved boundaries, present behavior is not a sufficient statistic for declared future learning.
Figures & tables
| Empirical object | Evidence supported by the frozen studies | Status |
|---|---|---|
| Local action and finite return | Action-specific one-step backbone; longer-horizon first-return non-closure. | Supported, local |
| Visible-relative completion | Fresh histories reproduce visible response, output-range reuse, and a low-rank irreducible-new sector in both models. | Supported |
| Re-anchored path transport | No path effect is resolved above the independent-bank floor; most ambient relative transports are ill conditioned. | Not resolved |
| Hard-switching chronology | Crossing, Hodge, bridge, and smooth-control diagnostics support the mechanism and prospective contraction. | Strict conjunction unmet |
| Adam accessibility | Mistral matched sections are accessible in the frozen chart; joint Qwen–Mistral panel membership is not established. | Context/metric dependent |
| Future-gradient revelation | Nonzero responses, zero-gradient controls, amplitude scaling, and analytic recurrence support de-cancellation. | Supported in Mistral |
| Premise | Not implied | |
|---|---|---|
| Present-behavior equality | future-learning equality | |
| Set-level quotient transport | stable ambient linear transport | |
| Asymptotic membership | exact finite-grid exponent | |
| Algebraic moment reachability | neural-data accessibility | |
| Surjective control differential | arbitrary raw-coordinate condition threshold | |
| Positive future observability | positive cross-bank directional coherence |
Appendix figures & tables5 assets
Supplementary material from the paper’s appendix.
Appendix
| Formal study name | Role in the paper |
|---|---|
| Local action and return structure | Establishes an action-specific local backbone, first-return non-closure, low local return rank, and the boundary of a fixed context-independent propagator. |
| Fresh visible-relative completion replication | Independently replicates visible/reuse/irreducible-new response completion in both models. |
| Re-anchored path-transport study | Tests a finite linear transport/monodromy membership after exact endpoint re-anchoring. |
| Controlled hard-switching scaling study | Tests crossing counts, marks, graph-Hodge cycle scaling, future bridges, smooth controls, and prospective finite-scale convergence. |
| Joint matched-section accessibility screen | Tests natural tangent alignment and joint Qwen–Mistral membership in a frozen two-step, three-coordinate control chart. |
| Conditional matched-section revelation study | Tests future-gradient de-cancellation in the empirically accessible Mistral subclass. |
| Study | Frozen outcome | Status |
|---|---|---|
| Local action and return structure | Fresh Qwen/Mistral histories support action-specific local maps. The one-step law extends, but a fixed closed three-dimensional two-step cocycle is not supported. The full first-return system has ; shifted-H6 low rank replicates. | Supported / boundary |
| Fresh visible-relative completion replication | At H5, median response energy is 60.29% visible, 23.99% reuse, and 15.72% irreducible-new. At shifted H6 it is 67.15%, 19.73%, and 13.13%. Both models satisfy the frozen replication without pooling rescue. | Supported |
| Re-anchored path-transport study | Mean cross-bank energy ; one-sided lower bound ; synchronized sign ; median SNR ; one of twelve principal relative-transport condition checks passes. | Not supported |
| Controlled hard-switching scaling study | Initial cycle approximately and softplus . Refined cycle , future bridges near , and softplus . Primary cycle equivalence holds, but four narrow conjunction criteria remain outside their frozen bands. | Mixed |
| Joint matched-section accessibility screen | Natural tangent alignment is high. Mistral satisfies the frozen first-slot screen for all six candidate seeds; Qwen satisfies none under the declared raw Euclidean conditioning criterion. No future outcome is computed. | Criterion not met |
| Conditional matched-section revelation study | Six Mistral chronology slots are dynamically reconstructed; twelve of twelve full-amplitude responses are nonzero; full zero-gradient controls are zero; median full/half norm ratio ; median full/half cosine . A bank-invariant direction is not supported. | Mixed |
| Horizon | Visible | Reuse | Irreducible-new | Median |
|---|---|---|---|---|
| Source H5 | 60.29% | 23.99% | 15.72% | 3 |
| Shifted H6 | 67.15% | 19.73% | 13.13% | 3 |
| Topic | Licensed interpretation | Not licensed |
|---|---|---|
| Predictive state | Present behavior is not a sufficient statistic for declared future-learning responses. | A finite fingerprint recovers the complete physical neural state. |
| Global fiber | The predictive quotient functor has a canonical set-level category of elements; regular bundles are conditional. | The measured Transformer system is unconditionally a smooth fiber bundle. |
| Completion | Fresh response contains visible, reuse, and irreducible-new sectors relative to a frozen projector and metrics. | The irreducible rank is the true neural hidden dimension. |
| Transport | Quotient transport is canonical; empirical finite linear transport is support- and resolution-conditioned. | The negative path study proves path independence or identity monodromy. |
| Switching | The controlled hard-ReLU system supports the proposed Hodge– mechanism and second-order approach while missing its full finite-grid conjunction. | Native Qwen or Mistral training universally obeys a law. |
| Adam | An exact algebraic matched section exists; accessible Mistral sections show future-gradient-conditioned revelation. | Generic natural reachability or a bank-invariant revelation direction. |
| Result | Required | Not required |
|---|---|---|
| Predictive quotient and global opfibration | Complete composition and prefix-compatible probes | Topology, probability, smoothness |
| Prefix-depth filtration | Declared prefix action readouts | Differentiability |
| Visible-relative completion | Finite-dimensional Hilbert metrics and a declared visible projector | Global bundle |
| History bridge | History chart and covariance | Stationarity |
| Hodge interaction isolation | Finite task graph and common-affine memory channel | Switching assumptions |
| Graph-projected law | Crossing covariance, centering, and aggregate dependence conditions | Transformer or ReLU by name |
Hidden-State Probing
Hidden-state probing reads model activations to study what they represent and whether those signals support monitoring or control.
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