Noodling around in string theory.

Byline: Greg Bolt The Register-Guard

S. James Gates considers himself something of a heretic in the Church of High Physics.

The University of Maryland professor is one of the nation's pre-eminent theoretical physicists and a leading believer in the mind-bending "theory of everything" known as superstring theory. But even as he preaches the superstring gospel and marvels over the "beautiful resonance" of its mathematics, Gates isn't afraid to sermonize on the theory's obvious flaw: It is not only unproven; for the time being, it is unprovable.

"As I tell my students when I teach a freshman class in physics, physics is not what I write on the blackboard. It's what is measured in the laboratory," Gates said in a telephone interview. `So although we can have this sense that (string theory) is correct, it won't be until someone sees it in the laboratory.'

Gates will bring his ideas about the universe and thoughts on Albert Einstein's contributions to physics to the University of Oregon on Sunday, when the school marks the start of the academic year with its annual convocation event. His talk, "Einstein's Lesson for the Third Millennium," begins at 3 p.m. in McArthur Court and is free and open to the public.

Gates is a sought-after speaker not only because of his explorations on the frontiers of science but also for an ability to explain the bizarre landscape of particle - and nonparticle - physics to a general audience. He is making almost 50 presentations this year as part of the World Year of Physics, will be in an Oct. 11 "NOVA" special titled "Einstein's Big Idea" and was featured on the PBS series "The Elegant Universe."

What excites Gates about superstring theory - also known as M-theory or simply string theory - is its ability to do the thing Einstein could not: unify the two realms of physics that explain how the most basic forces in the universe operate. As it stands now, scientists use the theory of gravity to explain the interactions of really big objects, such as stars and planets, and quantum theory to explain the behavior of ultra-tiny atoms and sub-atomic particles.

The problem is, the two theories don't play well together. When scientists try to combine the equations from the two theories to come up with a single blueprint for why the universe is the way it is, all they get is gobbledygook.

"So you have these two giant pillars of physics, and yet they're incompatible," Gates said. "In order for us as humans to get a complete picture, we've got to resolve this. String theory looks to be our best hope."

That's because string theory goes beyond the "billiard ball physics" that has governed our understanding of how the universe works from the ancient Greeks through Einstein. It proposes that everything, from the particles that make up planets and people to time and space itself, is made of exquisitely tiny, vibrating strings, or, as Gates sometimes calls them, "pastas."

"The old picture of physics essentially involved figuring out how tiny balls bounced off of each other. That's really what Newton did, that's really how we got to the moon," Gates said. "Well, instead of watching little balls bounce off of each other, you should begin to watch these little pastas, because the mathematics of pasta is very similar to the mathematics of string theory."

If true, the idea gives new meaning to the words angel-hair pasta. But what makes the theory sing, at least for the nontheoretical physicist, is not the string but the vibration, which would determine which of the building blocks of nature the string would compose.

"If you make them vibrate one way, you might get an electron," Gates explains. "If they vibrate another way, you might see that as a particle of light; it vibrates another way and maybe it's one of the quarks in a proton needed to make an atom in your body; it vibrates another way and it creates space; it vibrates another way and it creates time. If these objects are there, they are the most fundamental part of our universe."

That's still a big "if." Right now, scientists have no way to produce any evidence that would back up the theory. That led one Nobel-winning physicist to label it "the theory of everything that predicts nothing."

One reason the theory is so hard to prove is that strings have to be smaller than anything science has ever conceived of. To make a comparison, the difference in size between a human being and a proton isn't as large as the difference in size between a proton and a string.

It already costs billions of dollars to build an instrument powerful enough to study protons. Gates said it would take "all of the money I can conceive of" to build something to probe the structure of strings.

Besides, we don't even know how to do it. The only time when string theory would have been completely obvious was at the Big Bang, and presumably no one was around to see that.

Some things may point the way, however. A device called the Large Hadron Collider being built in Switzerland might soon show evidence of something called a superpartner, a new form of energy and matter predicted by string theory.

And examining the faint heat left over from the Big Bang also might reveal evidence of strings. Known as the cosmic microwave background, it's considered a faint snapshot of the early universe and could, like a kind of cosmological fossil, have evidence of strings imprinted upon it, Gates said.

But even if it does, so what? Why, as Gates himself poses, should people care about "these mad scientists running around the world saying strange things to each other?"

Well, technology, for one thing. And technology's close relative: hard cash. As Gates likes to say, physics is like the DNA of technology; it's what led to radio and television and cell phones and spaceships and the improvements in quality of life and standard of living that those things represent.

Gates quotes one commentator who estimated that at least a third of the domestic American economy is in some way connected with moving electrons back and forth - telecommunications, electrical power and computers are only part of it - made possible by technologies arising from physical laws uncovered more than 100 years ago.

If string theory can be proved, it will lead to a new understanding of the relationship between space and time. That, in turn, could lead to technologies unimagined now, just as cell phones were when James Maxwell developed the equations predicting the existence of electromagnetic waves in the 1870s.

Warp drive spaceships aren't possible if Einstein is right. But if string theory is right? Maybe.

"One way I've explained this to people is that the first person who understands how to build a starship will likely be studying the equations of string theory or something very much like it," Gates said.

But technology profits and science-fiction-come-true spaceships aside, string theory could strike at something far more basic, and in essence, far more valuable. We already know that the very atoms that make up our bodies - and all of the other atoms in the universe - come from stellar cradles and supernovas, but string theory would take that relationship a light year further.

"If string theory is correct, our connection to the universe is going to be much more intimate," Gates said. "It's not that we would just be related to the stars. We would be related to everything, including space and time, in some mysterious, almost metaphysical sense. And this understanding of our place in our universe is something that, although it may not yield practical results, it certainly speaks to how much a part of the universe humanity can be."