Writing study: Non-Euclidean Gradient Descent Operates at the Edge of Stability
← ICML 2026 oral writing corpus
Rustem Islamov, Michael Crawshaw, Jeremy Cohen, Robert M. Gower · Official ICML 2026 oral record
Figure, table and section ledger
Editorial contribution type: Theory & formal analysis (primary).
Layout extraction, not a required paper template. Counts are distinct caption labels; a multi-panel figure counts once. Section spans are estimated from heading positions, including floats and whitespace. Method and limitations.
- Canonical PDF
- 27 physical pages
- Before references / appendix
- ≈ 8.75 page-equivalents
- Main figures / tables
- 6 / 0
- Attached appendix figures / tables
- 13 / 0
- Attached appendix span
- ≈ 15.91 page-equivalents
Section-by-section lengths and source pages
The title/abstract/front matter precede the first numbered heading. A span ends at the next detected top-level heading, not at the last sentence; end-page whitespace is included. References and statements are listed separately. These are not measurements of text-only or artwork area.
| Top-level heading | Starts on PDF page | Estimated span | Share of entire PDF |
|---|---|---|---|
| 1. Introduction | 1 | ≈ 1.73 pp. | 6.41% |
| 2. Progressive Sharpening and Directional | 3 | ≈ 1.34 pp. | 4.96% |
| 3. Examples of Non-Euclidean Gradient | 4 | ≈ 2.91 pp. | 10.78% |
| 4. Normalized Non-Euclidean Gradient | 7 | ≈ 0.52 pp. | 1.93% |
| 5. Towards Understanding the Underlying | 7 | ≈ 1.5 pp. | 5.56% |
| 6. Conclusion and Future Work | 9 | ≈ 0.33 pp. | 1.22% |
| Impact Statement | 9 | ≈ 0.08 pp. | 0.3% |
| References | 9 | ≈ 2.34 pp. | 8.67% |
| A. Discussion on Frank-Wolfe Algorithm | 12 | ≈ 0.54 pp. | 2% |
| B. An oscillatory regime before EoS | 12 | ≈ 0.96 pp. | 3.56% |
| C. The gap between the generalized sharpness and 2/η | 13 | ≈ 0.67 pp. | 2.48% |
| D. Training Details | 14 | ≈ 0.13 pp. | 0.48% |
| E. Additional Experimental Results with ℓ∞ Descent | 14 | ≈ 1.33 pp. | 4.93% |
| F. Additional Experimental Results with Block Gradient Descent | 15 | ≈ 1.13 pp. | 4.19% |
| G. Additional Experimental Results with Spectral Gradient Descent | 16 | ≈ 2.26 pp. | 8.37% |
| H. ℓ∞-descent and RMSprop | 19 | ≈ 0.6 pp. | 2.22% |
| I. Useful Lemmas | 19 | ≈ 4.4 pp. | 16.3% |
| J. Non-Euclidean Gradient Descent on Quadratics | 24 | ≈ 3.91 pp. | 14.48% |
All detected figure and table locations
Argument and organization
- 1 Introduction; 2 Progressive Sharpening and Directional Smoothness
Defines the update geometry and links loss change to a directional quantity before introducing generalized sharpness.
- 3 Examples; 4 Normalized Non-Euclidean Gradient Descent
Recovers known cases and compares new norms using repeated diagnostic panels.
- 5 Towards Understanding the Underlying Mechanism; 6 Conclusion and Future Work
Uses quadratic stability results and a Taylor-switch experiment, then separates established facts from open mechanisms.
Problem, claim and contribution
The contribution is a geometry-aware diagnostic, not a claim that a new optimizer improves test performance.
Sections 1–2, physical pp.1–3 · Main paper
Argument and section order
Definitions, familiar special cases, new geometries and a restricted mechanistic result form an explicit progression.
Sections 2–5, pp.3–8 · Main paper
Figures, captions and visual explanation
Repeated columns align loss, gradient norm, directional smoothness and generalized sharpness; the later intervention switches from the real objective to a local quadratic approximation.
Figures 2–3, p.6; Figures 5–6, p.8 · Main paper
Tables, comparisons and evidence
Experiments are full-batch and sharpness can be an approximate nonconvex optimization result. The main paper distinguishes observed hovering from exact identities and conditional quadratic theorems.
Section 3, p.4; Theorems 5.1–5.2, pp.8–9 · Main paper
Appendix and reproducibility
Approximation discussion says stationarity is not global optimality; restart sensitivity and precise full-batch training defaults support interpretation of the plotted diagnostic.
Appendix A, p.12; D–E, p.14 · Main paper
Clarity and writing conventions
The conclusion explicitly states that divergence above the threshold is constructed for a particular initialization, not proved generic for every non-Euclidean trajectory.
Section 5 continuation and Section 6, p.9 · Main paper
What to reuse—and what not to infer
Transferable lesson: Use consistent diagnostic panels across cases, then distinguish an exact identity, a heuristic estimate, a theorem under assumptions and an empirical mechanism test.
Boundary: This is full-batch evidence, not a guarantee for stochastic, momentum-based or adaptive large-scale training. Frank–Wolfe estimates can understate generalized sharpness, and the divergence construction does not prove generic divergence. Formal proofs were not independently verified.
Apply this lesson using the argument and evidence worksheet.
Inspection record and sources
- Checked
- 2026-10-07
- Reading status
- Writing-focused manuscript scan + selected visuals inspected
- Main text
- Writing-focused scan across physical PDF pp.1–9, covering framing, section progression, definitions, method/evidence explanations, captions and scope. Physical pages extracted individually to avoid form-feed pagination errors. Selected full-page rasters inspected; not exhaustive line-by-line technical verification or experimental reproduction.
- Appendix / supplement
- Appendix heading inventory A–J checked; selected detailed reading of Frank–Wolfe approximation and pre-EoS oscillations A–B (p.12), and training/estimator sensitivity D–E (p.14). Full norm-specific derivations and quadratic proofs were not independently verified.
- Visually inspected PDF pages
- 6, 8
This is a writing-focused scan of the manuscript and the stated supplementary scope: framing, organization, visual explanation, evidence presentation and wording. It is not a line-by-line proof audit, reproduction of results or exhaustive scientific review.