Sizing Up the Universe

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By Joel Achenbach
Sunday, February 18, 2007

Wearing my science writer's hat (actually, it's a beanie with a propeller), I've been spending a lot of time lately interviewing particle physicists. They're very smart people who unfortunately tend to talk about "quantum chromodynamics" a bit promiscuously. They discuss muons, bosons, leptons, fermions, gluons and various other kinds of shmutzions that I can never keep straight. Fortunately, they're tolerant of idiots, and don't seem to mind when I ask questions like, "So how big, exactly, is a smithereen?"

Recently I visited Fermilab, a government complex west of Chicago where scientists smash together particles to see what kind of nifty stuff will spurt out. They use a collider called the Tevatron, which is 6 kilometers (11,765 miles, by my back-of-the-envelope calculation) in circumference. Big science is employed to make little particles into littler particles. The collider is hidden under a berm that circles a tall-grass prairie. An adjacent farm has a small herd of buffalo, who are no doubt worried that they'll be put into the collider and smashed into cows to produce beefalo.

Nature is incorrigibly complicated, and there's a list of things that continue to perplex physicists. They're not yet sure what the universe is made of at the fundamental level. They're not sure why the universe exists at all. Or whether there are parallel universes or hidden dimensions. Even gravity remains enigmatic. It's extremely confounding stuff if you're a physicist -- but it's also job security.

Fortunately, the universe has the remarkable quality of being constructed in such a way as to be describable with chalk. Physicists always carry chalk, and you rarely see them more than 15 paces (23 cubits) from a chalkboard. Clearly whoever put this particular cosmos together had some kind of teaching gig.

One of the things particle physicists have learned is that the universe contains a lot of nothingness. It's mostly empty out in space, and mostly empty even inside the atom. The Tevatron tries to crash protons into anti-protons, but the particles tend to miss one another or just whoosh right through each other without the really interesting chunky parts, the fabled quarks, coming into contact, and the collision is something of a dud. The one predictable effect is that some boring ol' gluons will fly out. No one cares about gluons. It's like having a vicious pillow fight that results in nothing but a few feathers drifting to the floor.

The collider and its powerful particle beam are hidden behind protective walls. The visitor sees pipes, cables, humming machinery. There's a control room with lots of monitors. What you can't see are the exotic particles. You can't catch some in a vial and sell them in a gift shop. Not only are they way too small, they're unstable and decay in a jiffy (7.3 nanoseconds). Also, we're way, way too big to be messing with these things intimately. We're bloated creatures trapped in the macro world. Compared with an efficient little particle, we're all enormous, sloppy, jiggly sacks of goo.

As huge, blobby organisms, we should probably be more appreciative of the tiny particles and unseen forces that make our existence possible. Most of us know a wee bit about the Periodic Table, which lists all the named elements very neatly by number, but we pay no attention to its equivalent in physics, the Standard Model. The Standard Model isn't quite as orderly as the Periodic Table. In fact, it's kind of raggedy. It has all these odd components, strange stuff that you'd expect to find in that Dr. Seuss book One Fish Two Fish . . . "From here to there, funny things are everywhere."

But maybe that's another thing we should be happy about: If the universe were purged of all its ungainly eccentricities, it might be nothing but pure energy. It might be a beautiful, glowing, heavenly cosmos without the interesting quirks.

Fermilab theorist Joe Lykken told me, "Elegant laws of physics give you boring universes that don't have anything in them."

So we'll take this universe, which, while difficult to understand, is still capable of producing astounding miracles -- such as human beings and Tevatrons.

Read Joel Achenbach weekdays at washingtonpost.com/achenblog.


© 2007 The Washington Post Company

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