The Scientific and Human Drama Behind the Higgs Nobel Prize

The state of the universe.
Oct. 8 2013 4:41 PM

Why the Higgs Is Such a Big Deal

But under no circumstances should you call it “the God particle.”

Francois Englert and Peter Higgs
François Englert, left, and Peter Higgs have won the Nobel Prize in physics for predicting the presence of the Higgs bozon, but at least four other contemporaneous theorists could make legitimate claim to the prize.

Photo by Denis Balibouse/Reuters

This morning, to the nearly universal expectations of the physics community, the 2013 Nobel Prize in physics was awarded to François Englert and Peter Higgs for the theoretical prediction of what has come to be known as the Higgs boson. Nobel Prizes (at least in the sciences) are almost always given out for a discovery rather than a prediction, so it wasn’t until last year, when two independent groups at the Large Hadron Collider detected the eponymous particle, that Englert and Higgs were even in contention. This year’s announcement represents an incredibly quick turnaround for a committee that has generally been fairly conservative in its awards. Einstein had to wait 16 years for his.

I’d like to share some cocktail party chatter on why the Higgs is such a big deal, what it means for the future of Big Science, and perhaps most importantly, why you should, under no circumstances, call it “the God particle.”

The Big Idea

Advertisement

As it’s normally described in the press, the Higgs boson gives mass to other particles, but it’s much more than that. The “Standard Model of Physics” is a mathematical description of every fundamental particle and interaction of nature (except gravity—so far, only Einstein’s theory of general relativity manages to get gravity right). The Higgs is the last piece of a puzzle, the final particle to be discovered in the Standard Model—and with the right sort of properties that we’d predicted from the start.

The Higgs boson is also the answer to a riddle: Why is the weak nuclear interaction, the interaction that controls (among much else) the fusion in the interior of the sun, so weak? Some forces, like electricity and magnetism, can extend over vast distances—your compass, for instance, responds to magnetic fields on a global scale—but the weak force is confined to the nuclei of atoms.

The weakness of the weak force is more than just a byproduct of the name. For the last half-century, we’ve understood the fundamental interactions of physics to arise when two particles exchange a “mediator,” basically a messenger particle that tells two electrons (for example) whether they should attract or repel one another. For electricity, the mediator is known as a photon, the particle of light. The photon is completely massless, which is why it’s able to travel so fast and so far. Indeed, a fundamental feature of the Standard Model is that all of the mediators are supposed to massless.

For electromagnetism and the “strong force” that holds protons and neutrons together, the mediators are massless, but the weak interaction is very different. In the weak interaction, the mediator particles are known, a tad unimaginatively, as the W and Z bosons, and when they were discovered 40 years ago, they were found to have a mass roughly a hundred times as much as a proton. In the particle physics world, this is huge—although marginally lighter than the Higgs boson itself. The relative bulkiness of the Ws and Zs is what ultimately confines them to atomic nuclei.

The “Higgs mechanism” aims to explain where all of that mass comes from.

How does the Higgs give mass? There is no shortage of analogies. Some have likened it to water that saturates sponges to make them heavier, or to a cosmic pool of molasses that slows down all particles that move through it, or to a celebrity thronged by admirers as she enters a room (the Higgs bosons are the admirers). All of these approaches aim to describe mass in terms of its consequences: Massive things, all things being equal, travel slower than massless things. Peter Higgs himself has described the mechanism as slowing down particles in the same way that a beam of light is slowed as it travels through a piece of glass.

Pick your analogy; they’re all imperfect. If the Higgs really were like molasses, then particles would not only slow down, they’d keep slowing until they came to a stop. But as Newton taught us, objects in motion stay in motion.

So skip the analogies and instead think of the Higgs as just another mediator particle, but with a twist: It allows the W and Z particles to interact with themselves rather than with another particle. To a physicist, an interaction is just a fancy way of introducing energy to the equation. And that equation is the most famous one in all of physics: E=mc2.

Einstein’s equation says a lot. For instance, by taking hydrogen and converting it to helium (as happens in the sun), there’s a reduction in mass, and that deficit produces a huge amount of energy.

The process works in reverse as well. Introduce enough energy (and you need a lot to make a difference), and the energy behaves the same as ordinary mass. In fact, this is where you came from. In the early universe, there was so much energy flying around in the form of massless photons that when they collided with one another, they were able to produce fundamental particles like electrons and quarks from whole cloth.

The Higgs doesn’t just pump up the mass for W and Z bosons. All fundamental particles should naturally be massless according to the Standard Model, but they aren’t. The Higgs is ultimately responsible for not only the mass of the W and Z particles, but all of the electrons and quarks in your being.

And that is a very big deal.

TODAY IN SLATE

War Stories

The Right Target

Why Obama’s airstrikes against ISIS may be more effective than people expect.

Why Is This Mother in Prison for Helping Her Daughter Get an Abortion?

The XX Factor
Sept. 23 2014 11:13 AM Why Is This Mother in Prison for Helping Her Daughter Get an Abortion?

Divestment Is Fine but Mostly Symbolic. There’s a Better Way for Universities to Fight Climate Change.

I Stand With Emma Watson on Women’s Rights

Even though I know I’m going to get flak for it.

It Is Very Stupid to Compare Hope Solo to Ray Rice

Building a Better Workplace

In Defense of HR

Startups and small businesses shouldn’t skip over a human resources department.

It’s Legal for Obama to Bomb Syria Because He Says It Is

How Ted Cruz and Scott Brown Misunderstand What It Means to Be an American Citizen

  News & Politics
War Stories
Sept. 23 2014 4:04 PM The Right Target Why Obama’s airstrikes against ISIS may be more effective than people expect.
  Business
Moneybox
Sept. 23 2014 2:08 PM Home Depot’s Former Lead Security Engineer Had a Legacy of Sabotage
  Life
Outward
Sept. 23 2014 1:57 PM Would a Second Sarkozy Presidency End Marriage Equality in France?
  Double X
The XX Factor
Sept. 23 2014 2:32 PM Politico Asks: Why Is Gabby Giffords So “Ruthless” on Gun Control?
  Slate Plus
Political Gabfest
Sept. 23 2014 3:04 PM Chicago Gabfest How to get your tickets before anyone else.
  Arts
Brow Beat
Sept. 23 2014 4:45 PM Why Is Autumn the Only Season With Two Names?
  Technology
Future Tense
Sept. 23 2014 1:50 PM Oh, the Futility! Frogs Try to Catch Worms off of an iPhone Video.
  Health & Science
Science
Sept. 23 2014 4:33 PM Who Deserves Those 4 Inches of Airplane Seat Space? An investigation into the economics of reclining.
  Sports
Sports Nut
Sept. 18 2014 11:42 AM Grandmaster Clash One of the most amazing feats in chess history just happened, and no one noticed.