Experiments this delicate are very difficult to get right. And it is very difficult to overstate just how much established physics would have to be scrapped if

Experiments this delicate are very difficult to get right. And it is very difficult to overstate just how much established physics would have to be scrapped if momentum conservation turned out to be violated. (Just for starters, relativity implies that non-conservation of momentum in one frame must always involve non-conservation of energy in another.) Why would quantum field theory calculations match experiment to ~12 digits of accuracy if its basic foundations were flawed? (Those calculations are affected by literally every possible quantum vacuum effect, so why wouldn't introducing some new set of momentum violating interactions completely throw off the results?) This is an astoundingly extraordinary claim, and it should thus require tremendously compelling evidence. I'm not at all convinced that these experiments are clean enough or consistent enough to even approach that standard.