⟨M| eo |w⟩?
Hmmm ... if I understand well then, this Amazonian study concerns challenges related to entangled quantum cat oscillators, with grainy amplitudes, hanging together in a box, by their tails, under an apparatus that might send them to meet their maker, or not, within the hour. The cats might shift around and flip about causing errors in the device's operation whereby, if experiments are run 100 times, the observed probability of finding cats in given states won't match the expected %50 predicted by theory, at all (a major issue).
To help with this then, you concatenate the cats with fluffy transmons, adding in extra cat-transmons to maintain a distance-5 relative position between them, eventually forming an ocelot-centipede that properly stuffs the whole box and then ... WaMmO! ... no more flip and shift errors. That's brilliant iiuc, especially for superconducting cats that are so hard to herd, even when stuck in a box ... but I'd suggest thinking of the cats a wee qubit, and maybe doing these experiments with bosons instead, or somesuch, imho!