Most people would think that the existence of the Higgs boson has been established. After all, the reports of its detection were announced with great fanfare in 2102 and two of the theorists involved in predicting its existence were awarded the Nobel prize in 2013.
But scientists rarely simply accept a result and move on. They look to see if there is confirmatory evidence using the standard method of hypothetico-deductive reasoning where they pose the question “If this result is true, what other things should we observe?” and then they go looking for them. If they find what they were looking for, then that adds to the evidence in favor of the original discovery. If they don’t find it, it casts some doubt and efforts are redoubled to try and resolve the discrepancy.
Those who recall the cold fusion episode will remember that after the initial reports of the discovery, it was the failure to find this kind of confirmatory evidence that led to doubt and eventual rejection of the idea. Much of scientific research involves this kind of cleaning up activity that takes place largely outside of the public eye. Major discoveries especially are subjected to this kind of close scrutiny.
In the case of the Higgs boson, according to theory, after it is produced it can decay into various modes. One consists of two photons and another consists of W and Z bosons, and both these decay modes had been observed as distinctive signatures of the existence of the Higgs in the discovery process. But the Higgs should, on occasion, also decay into a pair of fermions and now a paper from CERN reports that this decay has been seen at the 3.8 sigma level, meaning that there is only a chance of 1 in 10,000 that it could be a false positive.
This is how science works, always seeking new evidence that either corroborates or contradicts the existing paradigm. As I said in my debate with Joe Puckett, god is a lousy theory because religious people never do anything similar, like asking “If my god exists, what things should I expect to see?” and then go and look for them. And you can forget about statistical significance when it comes to god theories. People’s ‘feelings’ are seen as good enough.