Fourier transform inversion using an elementary differential equation\n and a contour integral
Bibliographic record
Abstract
Let $f$ be a function on the real line. The Fourier transform inversion\ntheorem is proved under the assumption that $f$ is absolutely continuous such\nthat $f$ and $f'$ are Lebesgue integrable. A function $g$ is defined by\n$f'(t)-iwf(t)=g(t)$. This differential equation has a well known integral\nsolution using the Heaviside step function. An elementary calculation with\nresidues is used to write the Heaviside step function as a simple contour\nintegral. The rest of the proof requires elementary manipulation of integrals.\nHence, the Fourier transform inversion theorem is proved with very little\nmachinery. With only minor changes the method is also used to prove the\ninversion theorem for functions of several variables and to prove Riemann's\nlocalization theorem.\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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 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".