The yes came from a member of one of two CERN teams competing to find the Higgs, Tommaso Dorigo. On his blog, Dorigo titled a post “Firm Evidence Of A Higgs Boson At Last!”
To that, Strassler said, “He’s out on a limb.”
The quarrel speaks to the nature of high-energy physics: It’s all about statistics. What sounds like certainty to just about everyone is anything but to a physicist. To claim a formal discovery, physicists want to see uncertainty squashed down to less than a one-in-a-million prospect.
“We consider ourselves the hardest of the hard sciences,” said Joe Lykken, a theoretical physicist on one of the CERN teams. “We are looking at literally mountains of data. The trouble is, the human eye finds patterns everywhere. If we don’t have very strong discipline, we’d find something in every plot.”
The scientific reconnaissance of small-scale, high-energy particles has been going on for more than a century. It was 100 years ago that Ernest Rutherford discovered the atomic nucleus; since then physicists have been diving deeper into the atom, looking for ever more basic structures from which the world is assembled. The search has had many triumphs, but it has become harder and more expensive as scientists seek to find particles that exist at smaller scales and higher energies.
The hunt for the Higgs is Big Science in the extreme. The machine built to find it — the Large Hadron Collider — runs through a circular tunnel 17 miles long, deep beneath the pastures and villages flanking the border of Switzerland and France. It cost around $10 billion to construct, with the cost shared by dozens of countries, including the United States, which contributed $531 million. Some 6,000 physicists work on the two competing — and yet complementary — experiments searching for the Higgs, known as CMS and Atlas.
The two experiments are miles from each other in different portions of the LHC tunnel. Powerful magnets are threaded through the tunnel and bend beams of particles. The beams move in opposite directions and eventually smash into one another inside the huge CMS and Atlas detectors.
In the past year, the LHC has produced some 300 trillion collisions. And still it’s not enough. The search requires powerful computers looking for a Higgs-suggestive bump, or an “excess of events,” in some region of the data.
Such a bump has now appeared at a specific place, showing something with a mass of around 125 billion electron-volts, roughly 125 times the mass of a proton. If that’s the Higgs, it would support the Standard Model of particle physics and be in a range where further scrutiny might turn up more definitive proof.
If the Higgs were to be declared nonexistent, on the other hand, a gaping hole would exist in physicists’ explanation of nature’s deepest structure. That, in turn, would excite a huge sector of the physics community, sending scientists scurrying for ever-wilder theories of the nature of matter.
But the odds of the Higgs not existing have now shrunk dramatically. That’s because the LHC has steadily narrowed the range of possibilities for what the Higgs could be. Tuesday’s data squeeze those possibilities even more and point to a very specific kind of Higgs particle.
No doubt acutely aware of previous hugely heralded announcements of new subatomic particles that later evaporated, the CERN leaders deployed their words carefully. Be prudent. It’s preliminary. We need more data.
But at the end of a news conference Tuesday, Heuer allowed himself a moment of bluster. He predicted the hunt will end soon after the LHC — now fallow for winter — restarts in March. He said, “See you next year with a discovery.”