Working out with Heavyweights of Physics

Physicists can be a hard breed to pin down. Most tend to breathe mathematics, universal constants and experimental proof, and rarely do they deign to translate for the lay person. But recently some of the brightest minds in physics hit Vancouver, brought by the Pacific Institute of Theoretical Physics (a kind of physics talent agency) to UBC to speak, share and experiment with peers. One of the promises of their stay: three lectures directed towards the public.

I found that hard to resist. I have just one university level physics course under my belt, which is enough to stoke my curiosity but not to guarantee I'd understand much of anything said. As it turns out my curiosity was more than rewarded. The three scientists spoke of liquids that flow up walls, how to look into an atom and why we may all be Martians. Their talks were complicated at times, but each spoke directly to the need of the human mind to understand the universe.

Accept here, please, my best attempt to share their thinking with readers of The Tyee.

A frictionless contraption

Moses Chan, an experimental physicist and professor at Penn State, came to Vancouver to speak of a remarkable thing -- liquids and solids that don't experience friction.

Upon entering the lecture hall for Chan's talk, I beheld two metal plates suspended from a bar. In unison, these plates were slightly rotating from side to side, a video camera projecting their movements onto a large white screen.

The only clue to the purpose of this contraption was Chan's lecture title: "Einstein's legacy in low temperature physics; superfluids and supersolids". (Chan would later confess that although Einstein had a lot to do with low temperature physics, he did partly use his name to draw people into attending the lecture.)

Turns out this contraption is called a "torsional pendulum." Chan and his UBC colleague Walter Hardy, who machined the pendulum specifically for the lecture, used it to demonstrate the idea of superfluids -- a mysterious fluid that lacks friction and can flow up the sides of a cup.

I understood quickly why Chan's UBC colleague Philip Stamp, a Professor of Physics and Astronomy, calls him "quite a character," as Chan began to poke fun at Hardy, a physicist whose papers he was forced to read as a student and who was now acting as his assistant for the demonstration. "This is a highlight for me," said Chan.

The idea of the demonstration is that in a normal situation when you twist the bottom plate the top plate twists too, but in the case of a superfluid, when the bottom plate twists the top plate stays still because it lacks any friction.

So far so good, I understood that the lack of friction would allow the superfluid to be pulled up the walls of a cup. This is because a cup is covered with a microscope layer of the superfluid-like any cup with liquid in it, says Chan -- which is no longer held stationary by friction and begins to flow.

Chan and his colleagues recently discovered a solid, termed a supersolid, which does the same thing. "This loss of viscosity allows it [the supersolid] to move through a pore that is 70 angstroms," says Chan, "a normal fluid or solid would get instantly stuck." An angstrom is small too, in relation to a human hair, about 500,000 times smaller. These fluids and solids are definitely doing things normal matter can't.

"This is a spectacular discovery that most people believed to be impossible," says Stamp. Many people believe that Chan will one day win the Nobel Prize for finding a supersolid.

Little stuff, big eyes

Such oddities of matter are one thing, but understanding what this matter is made up of is another. In the second talk, Gerard 't Hooft, a Nobel Prize winner in 1999, tried to explain how we (or physicists at least) know what we know about the building blocks of matter -- information that could only come from gigantic and powerful machines.

't Hooft's talk was a tough one. Although he is a well-known figure in physics, in part due to the fact that he completed the work that would win him a Nobel Prize before finishing graduate school, 't Hooft faced the task of explaining a math-laden field of elementary particles to me. Nevertheless, he got me thinking about what would fall out if you cracked an atom like an egg.

"The universe is beautiful and spacious," says 't Hooft, from the Royal Dutch Academy of Sciences. "But there is also a whole universe within the atom," he says. This universe includes many particles, from quarks to gluons to photons, as well as 23 constants and natural laws.

Really understanding how these particles and forces work requires a lot of math, which 't Hooft declined to go into, and this was probably for the best, my seat that day was near the door. Nevertheless, theoretical work has organized elementary particles, and their interactions, into a 'standard model'. But it's much more than a model, says 't Hooft with some emphasis, it is a very accurate representation of reality.

The standard model provides guidance to physicists looking to study or find elementary particles. While my mind grasped to understand this, 't Hooft asked an interesting question that often passes people by: "If you want to study tiny things [like elementary particles], why not build tiny machines?"

Today, experimental physicists use huge particle accelerators -- the Large Hadron Collider at CERN is 27 km circle -- and particle detectors, which can be five times as tall as a human, to study elementary particles. But why are they so big?

Turns out, "the smaller things are the bigger eye you need," says 't Hooft. To study the atom (and thereby verify the 'standard model') you therefore need very large machines.

Are we from Mars?

In the last talk, Paul Davies made the intriguing suggestion that maybe life didn't start on Earth at all. Instead, Mars could be our ancestral home.

Davies', a cosmologist at the Australian Centre for Astrobiology, is already a media star, having authored several popular books over the years, including How to Build a Time Machine. And it showed in the heavy attendance at this talk and light tone he struck while tackling the question of the "origin of life".

"Why should we care about the origin of life," asks Davies. Well, it leads to one of the deepest philosophical questions around, "Are we alone in the universe?" Currently, we are quite ignorant of the answer to this idea, says Davies.

However, part of the answer lies in whether life originated on Earth, or somewhere else in the Universe and subsequently seeded our planet. The reason this is even a question, explains Davies, is due to the paradox that life appeared on Earth during a period of heavy bombardment with asteroids. A period not that conducive to the formation of life, says Davies.

Instead, Davies suggests that Mars was a much better place to start life. An idea bolstered by recent evidence suggesting that Mars has water.

"If life did start on Mars, than I think it is inevitable that it would have come to Earth," says Davies. The reason for that is that asteroid impacts would have sent rocks with life of it to Earth, he adds. Martian meteors have been found on Earth, but it is not yet clear whether they could have carried life here.

Answers to our origins may therefore lay in a future trip to the Red Planet, says Davies.

Who cares?

No matter which way you cut it, physics lectures are always going to be somewhat cerebral. But, they also have a knack for surprising you.

Many non-physicists attending the PIPT talks, like me, were left scratching their heads at moments, only to be pleasantly surprised seconds later by an interesting revelation. At the end of Chan's talk, one fellow asked: "I appear to be the only non-physicist here, but what is the practical application of supersolids?"

A slight smile on his face, Chan replied, "There is no practical application." Not yet at least. Nevertheless, its intellectual interest appears to be infinite.

It is this pure intellectual interest that often blocks experimental and theoretical physics from discussion in the public domain. And to be fair, physics is also difficult to understand at times. Nevertheless, I did get a few nuggets out of the each lecture. I therefore think the PIPT is doing a good public service in bringing physicists to Vancouver.

On my walk home, I mused about how little the average person is exposed to the fascinating thinking discussed in the lectures. Maybe we worry we'll strain ourselves by trying to pick up such big ideas. If so, that's too bad. After all, as Albert Einstein said, "the whole of science is nothing more than a refinement of everyday thinking."

(For those interested to learn more, the PIPT website is rich with information.)

Dave Secko is on staff at The Tyee.