Tuesday, April 04, 2006

Physics world buzzing over faster-than-ever particles

A major physics lab in the U.S. has found a particle, far smaller than any atom, that switches itself back and forth between being a piece of matter and a piece of anti-matter 17 trillion times each second.

It has taken 700 people in 20 countries, millions of dollars' worth of custom equipment, vast amounts of energy, and 20 years of work to find this.

The back-and-forth switching appears to be one of the fastest processes in nature. One of the big mysteries in physics is why the universe is practically all matter, and not anti-matter. The universe once had equal amounts of both, scientists believe.

So where did the anti-matter go?

And while the physics world has been buzzing since Thursday's announcement of the latest anti-matter find, outsiders have barely noticed.

Why?

The experiment illustrates the difficulty in publicizing work in this abstract world of concepts unknown to most people -- quarks, muons, particle accelerators, and anti-matter itself.

The finding at Fermilab, a U.S. federal physics laboratory, is never going to affect your daily life. Fermilab found a particle called a "B-sub-s meson." You won't ever buy an iPod made of B-sub-s mesons. And Fermilab's announcement was pure gobbledygook, which didn't help.

The work's significance? "This measurement has confirmed the Standard Model," says physicist Wendy Taylor of York University, one of the 700 who toiled on the experiment.

The Standard Model is the basic theory that physics has used for 30-plus years to explain particle physics.

But, she adds, finding the B-sub-s doesn't go as far as many had hoped in explaining mysteries that still remain in physics, such as how things change between matter and anti-matter.

"We know there's physics beyond our current theory, and we're trying to find it," she says.

How, she's asked, should scientists tell the public all this?

Taylor, who holds a Canada Research Chair, sighs. "You would know that better than I do," she says. Maybe, she muses, if her team worked in cold fusion, an area ripe with juicy scandals, things would be different.

However, she finds the meson results "very cool."

Here's her anti-matter lecture for non-scientists.

"We have an idea what matter is, right? Something you can hold in your hand and touch and so on.

"Anti-matter is very similar. It has mass. But it has the opposite properties of matter," in particular, an electrical charge opposite to that of its "real" matter counterpart.

"What's interesting is that there isn't much anti-matter out there. And if you watch Star Trek, you know that when a matter comes into contact with its own anti-matter particle, they annihilate, and the mass gets converted into energy by the E=MC2 formula."

And now, a particle switches back and forth, because it contains a quark (even smaller than a meson) that itself goes between matter and anti-matter. A very few other particles also do this, but this is by far the fastest.

"If it had been completely on total disagreement with the Standard Model, then of course that would be the most exciting thing," the York physicist says. "We know there's something out there. We want to find it. But we have to keep looking."

The Fermilab paper has not yet been published.

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