This sort of time flip has been described as looking into a mirror and spotting your back instead of your face...By carefully adjusting electronic components on a strip of metal, they introduced a sudden jump that reversed the direction of incoming signals...The outcome was a time-reversed copy of the original wave, appearing just as predicted but never before seen with clarity...A wave that can jump to a new frequency and then rewind might open new possibilities for data transmission at different ranges of the spectrum. It could also reshape how certain sensors and imaging systems are designed.
I think the neat part isn't that - it's neat because of the time component doing it.
Yet another strange phenomenon of the quantum realm that seemed impossible but is infact real.
If I remember thinking back to my class on QED, we specifically ignored this solution because there wasn't a real world demonstration of it (which was ironic, as one of my professors was working on the problem in her doctorate).
Makes me want to find that book.
Edit: I might be wrong, I'm thinking of deriving something out of Hilbert Space to Dirac-von Neumann axioms