I have not yet read the linked paper, but seismologists have used the Schroedinger wave equation in seismic imaging since at least the 1970s [1], certainly a "c

I have not yet read the linked paper, but seismologists have used the Schroedinger wave equation in seismic imaging since at least the 1970s [1], certainly a "classical" system. [1] https://pubs.geoscienceworld.org/geophysics/article-abstract/36/3/467/71259/Toward-a-unified-theory-of-reflector-mapping https://pubs.geoscienceworld.org/geophysics/article-abstract...