I’ve just spent the afternoon watching CERN’s live webcast of the latest CMS and ATLAS data (thank you, CERN, for inventing the Web!). After today there’s very little room for the Higgs still to hide.
ATLAS essentially rules out the existence of a Higgs boson, unless the Higgs mass is in the region 115 to 131 GeV. (I guess I should say that, for comparison, the proton mass is about 1 GeV (actually 0.938 GeV)). CMS seems to rule out a Higgs that is more massive than 127 GeV.
What is tantalising is that both experiments saw hints of a Higgs at around about 125 GeV. Unfortunately, the signal was not strong enough to claim a discovery: what they saw might have been a statistical fluke.
The only way to decide the matter is to take more data which is, of course, what the two experiments will do. In a few months time we will know one way or the other. Either the bumps that ATLAS and CMS saw will go away, and we can say that the Higgs doesn’t exist. Or the bumps will get larger and clearer, and we can say that the Higgs exists with a mass of around 125 GeV.
Either way, new physics will be required. Either way, it will be the discovery of the century.