Second-order equations and local isometric immersions of\n pseudo-spherical surfaces
Bibliographic record
Abstract
We consider the class of differential equations that describe\npseudo-spherical surfaces of the form $u\\_t=F(u,u\\_x,u\\_{xx})$ and\n$u\\_{xt}=F(u, u\\_x)$ given in Chern-Tenenblat \\cite{ChernTenenblat} and\nRabelo-Tenenblat \\cite{RabeloTenenblat90}. We answer the following question:\nGiven a pseudo-spherical surface determined by a solution $u$ of such an\nequation, do the coefficients of the second fundamental form of the local\nisometric immersion in $\\mathbb{R}^3$ depend on a jet of finite order of $u$?\nWe show that, except for the sine-Gordon equation, where the coefficients\ndepend on a jet of order zero, for all other differential equations, whenever\nsuch an immersion exists, the coefficients are universal functions of $x$ and\n$t$, independent of $u$.\n
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.010 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.014 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".