COSI Blog
15
March
2013

A Higgs Update

LHC

A while ago we reported on the discovery of the Higgs particle at the Large Hadron Collider (LHC) in Europe. On March 14, CNN and other news outlets reported some new information to coincide with both pi day (3.14) and Albert Einstein's birthday.

So what's it all about?

Back in July of 2012, scientists at the LHC reported that they'd found a particle that behaves very much like the Higgs particle. The Higgs particle is not so important in itself, but it gives us clues about the Higgs field, which is the field that gives you and me (and the particles that make us up) mass. They were able to find the Higgs particle ahead of schedule because of a surprising way in which the particle was decaying.

The best way to think of the Higgs particle is a disturbance (a wave or a wiggle) in the Higgs field. But this disturbance is very unstable. The Higgs particle survives in our world only a tiny fraction of a second, such a short time that we never see the particle itself – we only see the things it decays into. One of those "decay paths" is into two photons – two very high-energy pieces of light. The experiments at the LHC detected lots and lots of these two photon decays. In fact, it was because there were so many of them that the Higgs discovery could be announced so early in the experiment, long before many expected it.

This surprising result was exciting news for physicists. They were actually hoping to be wrong about the Higgs. They were hoping that some feature of the Higgs – such as its likelihood to decay into two photons – would be wrong. This would point them toward new physics, new ideas, new experiments to try. No one knew if this excess of two photon decays really was new physics, or if it was just luck, a little like rolling doubles three times in a row in Monopoly. Sure it's rare, but rare things do happen (that's what makes them rare and not impossible.)

The announcement on March 14 of this year was that the extra photon decays really were like rolling doubles three times. If you keep rolling, eventually the doubles streak goes away. That's what happened at the LHC. As they analyzed more and more data, the scientists found that the extra photon decay signal blended into the background. As far as that particular decay is concerned, the Higgs particle seems to behave just as theory would suggest. That's good, it means our theory works, but it's also disappointing, because physicists really, really want to be wrong. It'll tell them what to do next.

All is not lost, however. We know that our current theories of the world are far, far from complete. We know there are mysteries out there, such as dark matter and dark energy. We have no idea what they are, but we know they exist. We don't understand the mass of neutrinos, or of the Higgs particle itself. We don't yet know what caused the universe to suddenly expand over 13 billion years ago. And of course there's always the mystery of what is a "Q" and why do they only use the tip. There's lots more to learn, so keep watching!

blog comments powered by Disqus

Blog Authors