>>11174861post arXiv link
i'm just going to guess: this is like some super detailed cryogenic condensed matter thing and the "push" they put on it is some obscure thing like an oscillating magnetic field and the negative mass is measured in some other obsure way like a SQUID measurement with some complicated correlated background subtraction
yes yes, we all know, if you make some weird setup you can generate weird results. if your weird results resemble "negative mass", cool story bro, but that doesn't mean negative mass does real. just means cond-mat experimentalists try their hardest to make head-scratcher experimental results that popsci reports on real fast before anybody reads your paper, you cash in on the publicity, then a week or two later you get funding, then two weeks after that everyone explains away things but it doesn't matter since you already got them gibz
