It's barbecue season, and you need to sound smart while drinking beer around your charred meat. But how will you discuss the most important scientific news of the year — and maybe of the decade — if you don't know anything about it? It's okay. We're here to explain what "the God Particle" is, and whether or not the Europeans found it.
What is the God Particle?
The "God Particle" is the name physicist and author Leon Lederman gave to the Higgs boson in his book The God Particle: If the Universe Is the Answer, What Is the Question? It's meant to communicate the importance of the particle to "our" (LOL, like you and I have any clue) understanding of physics; Lederman has also said that he settled for "the God Particle" because his intended title, "the Goddamn Particle," was rejected by the publisher.
The news media has generally preferred calling it "the God particle" because who on earth in their right mind would ever read an article about "the Higgs boson"; also, the name pisses scientists off to no end, which is a good reason to keep using it, as often as posible.
Okay, but, in that case, what's the Higgs boson?
Well, at its simplest, it's a hypothetical particle that physicists believe gives all other particles mass.
Yeah: "Higgs boson" isn't the name of a particle that scientists have seen and observed and recorded with their enormous magic science binoculars; it's the name of a particle whose existence has been predicted by physicist Peter Higgs (among others: Robert Brout, François Englert, Gerald Guralnik, C.R. Hagen, and Tom Kibble).
He predicted it, like a fortune-teller? Like it's a hover-board, or something?
So, over the course of the last five or six decades, particle physicists have been developing a mathematical model for their field that explains, more or less, what the fundamental particles of the universe are and how they interact.
But because fundamental particles aren't the kind of thing you can rent a house for in Miami and watch as things get real, the Standard Model started as a reverse engineering of the universe, based on what we (haha, you know, "the collective knowledge of humanity," not Gawker Readers) could say was true with a reasonable degree of certainty thanks to experiments and what theorists could extrapolate from that — a series of sort of educated guesses, or predictions, about what the particles are and how they act at parties. It's a bit like being in a room, blindfolded, and having to draw a picture of its layout: you know one wall is here, and you bumped into another wall there, so you can figure out with varying degrees of certainty the location and size of the other walls, and where the corners are as well.
As scientists are able confirm the existence of certain particles through experimentation — in other words, find the other walls — and observe the ways those particles (or walls) deviate from what the Standard Model predicts, physicists are able to modify and refine their theory. In 1983, for example, physicists at CERN (the European Organization for Nuclear Research) found evidence of two bosons — the W and the Z — that had been predicted by Steven Weinberg, Sheldon Glashow and Abdus Salam when they laid out the Standard Model in the 1960s. It was a big deal.
And so the Standard Model predicts the existence of the Higgs boson?
Yes. In this sense, "predicts" means something like "requires in order to exist." It's the last particle left to be "seen" by scientists, and without it, the Standard Model doesn't really work. Physicists are hoping to observe (as best they can) the Higgs experimentally — or even better, something similar to, but slightly different from, the Higgs — to help confirm that they're on the Right Track.
Why would it be better if it wasn't the Higgs?
The hunt for evidence of the Higgs boson has been the major focus of particle physics for years now. If physicists find the Higgs exactly as it's predicted to exist in the Standard Model, it's kind of boring. They know that the model, being partially theoretical, is unlikely to be a completely accurate picture of the universe at the atomic level. If they can find a particle that does the same work and fulfills the same function as the (theoretical) Higgs, but has certain differences, it helps them modify and refine the Standard Model — which in turn helps point the way toward new work.
Okay. So what is "the work" that the Higgs does?
Like I said, it gives some of the other particles mass.
Okay. So. The Higgs boson is a quantum — the minimum possible amount — of this thing called the Higgs field. To paraphrase a famous scientist: the Higgs Field is what gives a particle its mass. It surrounds us and penetrates us. It binds the galaxy together. (Hypothetically, of course! Remember: we assume the Higgs Field exists because math that describes the universe very well wouldn't work if we didn't include the Higgs Field in it.)
Without the Higgs Field, all elementary particles — the six kinds of quarks, electrons and the other five leptons, photons, gluons and the Z and W bosons — would be massless and move at the speed of light. This would not be a very fun universe; or, it might be fun, but fun would be a meaningless concept because nothing would exist. With the Higgs Field, however, some particles slow down: in interacting with the field, they gain mass, and move through the field with more difficulty. (At this level, we should be aware, mass and size don't correlate; mass is a characteristic like electric charge and particles with different masses are the same size.)
Physicist John Ellis uses a winter sports-based analogy: the Higgs Field is like snow. Photons and other massless particles are like skiers, barely interacting with the snow and zipping around on it; slightly more massy particles are the snowshoers, who interact more with the snow and therefore move more slowly; and the massiest particles, like the Z boson, are people like you, totally unprepared, interacting heavily, and miserably, with the snow in boots, that probably have holes in them. And the snowflakes themselves —
— are the Higgs boson.
Exactly. The quanta that make up the field.
I still don't really get it.
That's okay! I have a bunch more analogies to try:
The Cocktail Party Analogy. This is one of the oldest, and most famous: imagine watching a cocktail party from above, because you are, say, a ghost, that floats above the cocktail party. Suddenly, a celebrity — Jesus, say, or Dog the Bounty Hunter — enters and starts to walk across the room. As the Jesus/Dog walks through the room, party guests cluster around him, slowing him down. At the same time, a non-celebrity — a Gawker blogger, for example — enters through another door and gathers no one: his speed is unhindered. In this analogy, the party is the Higgs Field, the partygoers are Higgs bosons, Dog the Bounty Hunter is a massy particle and the lonely Gawker blogger is a photon or something similar. (Note that in terms of human behavior I think this analogy works better set on the steps of a courthouse following a highly newsworthy trial, where the lawyers are massy particles and the reporters are Higgs bosons. I don't think that clustering-around-a-celebrity-at-a-party thing really happens, does it?)
The Sugar and Ping Pong Balls Analogy. In this great Guardian video, science writer Ian Sample puts a bunch of ping pong balls on a tray and shakes them. This is the universe before the Higgs field. He then pours sugar on the tray and puts the ping-pong balls back on; tray shaken, the balls now move more slowly, caught in the sugar. This is the Higgs field; the individual sugar grains are bosons.
The Pool Analogy. Physicist Don Lincoln compares the Higgs Field to a pool, and water molecules to Higgs bosons. Massy particles are like scientists and bloggers — awkward and slow in the pool; less massy particles are like barracudas: streamlined and quick.
Okay. This sort of makes sense, if I don't think about it too much. But how do we find a Higgs boson?
Right. Between 1998 and 2008, CERN built the world's largest (and highest-energy) particle accelerator, the imaginatively-named Large Hadron Collider. Basically it's a 17-mile elliptical tunnel 500 feet below the ground in which scientists can send particles flying at each other at insane, near-light-speed speeds.
When those particles collide at high speeds, their energy is transmuted into new, high-energy particles, like, scientists hope, the Higgs boson. Ideally, physicists could smash protons together until they created a Higgs and then take a photo and dust off their hands.
There are a few problems, though. One is that we can't really observe a Higgs boson directly — it almost instantaneously decays into other particles (bottom quarks, in this case) with the same mass as the Higgs. Furthermore, a lot of particles decay into the same byproduct, so even if you end up with bottom quarks you can't be exactly sure that they came from a Higgs. Another problem is that the Standard Model doesn't predict an exact mass for the Higgs, just a range.
So scientists need to observe millions and millions of collisions, and pay special attention to those collisions that end up as bottom quarks weighing (collectively) in the 122 giga electron volt to 130 giga electron volt (those are real units, I swear to God) range. They then compare those results to two predictions: one, the predicted results if the Higgs exists, and two, the predicted results if the Higgs doesn't. As scientists pile up more data, they can watch their figures hew more closely to one or the other theory. If their results look like the results of the "Higgs exists" prediction, they can say they've found it — or something like it.
So did they? Find it?
Well, no, but, basically yes.
Essentially what the physicists at CERN announced on Wednesday is that two different teams, each observing and processing data from particle collisions, had detected the existence of a particle with a mass around 125 GeV. (And, furthermore, that these detections have a one in 3.5 million chance — five standard deviations, or "five sigma," — of being a mistake.)
So really what the scientists have found is evidence that a "Higgslike" particle exists. They'll be spending the next several years fucking around with it to see how it ticks — in particular, like I said before, to see how it might deviate from the Standard Model's prediction.
And what happens if it deviates?
Who knows? Probably, we will open a wormhole in the atmosphere that leads to another dimension where people ride dinosaurs like horses.
No. But if it points us in a new direction that the Standard Model doesn't currently cover, we might be able to start explaining, in lengthy and performatively casual blog posts, stuff like why the universe is matter and not antimatter, or what dark matter is, exactly.
Would've liked to see dinosaurs, though.
Me too, man. Me too.
Do you know any jokes about the Higgs boson?
A Higgs boson walks into a Catholic church. The priest says "we don't allow hypothetical particles in here." The boson says, "but without me you can't have mass!"