Koopman's 1946 Search and Screening: the once-classified math behind DMD
PTenigma · x · 2026-11-02
A researcher revisits Koopman's classic Search and Screening (1946), a spectral math / dynamical systems text rarely cited today.
- Koopman moved from Paris to the US at 15 and pioneered the operator behind DMD.
- His book was classified by the military for its use in locating submarines.
- The 1946 text on allocating search effort also informs dynamical-systems analysis of fMRI.
- Bonus puzzle: can it guide curriculum learning or efficient sampling to compute stable DMD eigenvectors from fMRI?
The post includes many original search-pattern figures (spiral search, pursuit envelopes, probability contours, nomograms).
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