The Vienna group publishes on Nature Communications

We are used to the fact that events are sharply localised in time. In a cuckoo clock, the cuckoo always calls at a precise time. Everybody looking at the clock would agree on this. However, the TEQ Vienna team led by Caslav Brukner from the University of Vienna and the Austrian Academy of Sciences showed that, when quantum mechanics and Einstein’s general relativity are combined, this might no longer be the case. When time “goes quantum” the temporal localisability of events becomes relative. In quantum times, the cuckoo can call at a precise time according to one observer, but some other observers might be totally uncertain about the time when it sings.

Link to the publication: https://www.nature.com/articles/s41467-020-16013-1