I don't normally have much reason to care about the 4th of July -- it's a banal, masturbatory celebration of America, that mostly features explosions, drinking, and saccharine patriotism. This year, though, I've got a reason to mark the date: CERN is holding a press conference on Wednesday, and they might be announcing that they found the Higgs Boson.
The Daily Mail and the Associated Press have both declared that announcing the discovery of the Higgs is definitely what CERN intends to announce at the press conference. Nature, a substantially more credible scientific publication, reports that physicists have discovered a particle, but it's unclear whether it's the Higgs. Their article quotes one anonymous physicist, "Without a doubt, we have a discovery." So, whatever is happening on Wednesday, it's going to be good.
Another anonymous scientist, quoted later in the article, says,
In practice you would have to be monstrously sceptical not to be convinced by what we have now. But the final decisions on what to say on Wednesday are still being made.
But being very close to certain still doesn't qualify as being certain, and scientists quite rightly tend not to claim they're right until they're sure.
Physicists have maintained that they will not announce the discovery of the Higgs until the signal surpasses 5 sigma, meaning that it has just a 0.00006% chance of being wrong. The ATLAS and CMS experiments are each seeing signals between 4.5 and 5 sigma, just a whisker away from a solid discovery claim.
Even if they're right, though, the fun part, it seems, has not yet arrived:
Physicists will now turn their attention to understanding the new particle. Crucially, they will want to know whether it behaves like a mass-giving Higgs, and more specifically whether it behaves like the Higgs predicted in the standard model. One important task will be to carefully measure the different ways that the particle is produced and decays inside the LHC detectors.