Symbol of the Dirichlet-to-Neumann operator in 2D diffraction problems with large wavenumber
Bibliographic record
Abstract
Consider the Dirichlet-to-Neumann operator N in the exterior problem for the 2D Helmholtz equation outside a bounded domain with smooth boundary. Using parametrization of the boundary by normalized arclength, we treat N as a pseudodifferential operator on the unit circle. We study its discrete symbol. We put, forward a conjecture on the universal behaviour, independent of shape and curvature of the boundary, of the symbol as the wavenumber k /spl rarr/ /spl infin/. The conjecture is motivated by an explicit formula for circular boundary, and confirmed numerically for other shapes. It also agrees, on a physical level of rigor, with Kirchhoff's approximation. The conjecture, if true, opens new ways in numerical analysis of diffraction in the range of moderately high frequencies.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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".