Nobel Laureate David Gross spoke on upcoming breakthroughs and experiments in theoretical physics at the Buehler Alumni center on Tuesday evening.
The main focus of Gross‘ lecture, “The Coming Revolutions in Fundamental Physics,” was the highly-anticipated experiments and analyses of the Large Hadron Collider (LHC), an internationally-funded machine build in Geneva, Switzerland.
LHC experiments may teach us about what constitutes matter, the origin of the universe and confirm or disprove theories that have puzzled physicists for decades.
“There are all these heavy particles permeating in the universe and we don’t know what they are,” said Gross, who is the director of the Kavli Institute for Theoretical Physics at UC Santa Barbara. “So we’re going to look for them, and they will provide a hint of what might be there. Many of us suspect that there might be a very profound, new aspect of nature that will be revealed at the LHC.“
From the results of the machine, Gross said he hopes the mysteries of elementary particles – the basic building blocks of the nucleus of the atom – will be uncovered. This will help explain theories that have never before been experimentally tested, he said.
“[For] every particle that we have seen there’s one we haven’t seen, if not more,” Gross said. “And so if this [is] true … then the experiments will be fantastically interesting, and we’ll learn a lot.“
Specifically, Gross hopes to learn more about supersymmetry. This unproven symmetry of nature holds that for every subatomic particle, there exists an essential counterpart. Analysis of supersymmetry can give insights on quantum dimensions of space and time.
“One of the implications of supersymmetry is that we will learn more about the quanta of space and time,” Gross said.
The LHC is a collaborative effort, with over 100 countries contributing to its construction. The world’s largest and highest-energy particle accelerator, the LHC spans 17 miles in circumference — its detectors average five stories in height and funding for the project has exceeded $1 billion.
“You get these small particles and accelerate them into orbit, moving at the speed of light back and forth, around and around, billions of times a second,” Gross said. “The machine is cooled by helium at 1.9 Kelvin; it’s the coldest place of this size in the universe, probably.“
As an analogy, Gross explained that “the beam has so many protons going so fast with so much kinetic energy, that the total energy stored in the beam is equivalent [to] the kinetic energy of a small aircraft carrier, traveling through the water at 30 knots.
“Building [the LHC] is often compared to building the pyramids as they did 10,000 years ago,” he said. “It’s pushing the limit of what humans can do. This project is unimaginably complex and impressive.“
The LHC was speculated to start experiments last year, but has run into time-consuming problems, much to physicists‘ dismay.
“Problems occur when you build something that was never built before,” Gross said. “The first delay was lack of funding. But the second delay was because of an accident that happened last September.“
Last September scientists turned on the massive machine without error. But as the energy was increased, there was an electrical short.
“A copper wire carrying 20,000 amps shorted out and caused an explosion,” Gross said.
As a result, a vacuum tube was ruptured, releasing 50,000 tons of liquid helium from the delicate machine.
“We’re probably delayed a year,” Gross said, explaining the result of the accident. “We’ve been waiting such a long time.“
There was a large audience in the lecture, with patrons moving chairs to the aisles for a chance to see the Nobel Laureate. The audience consisted of students and local residents; there was also a large amount of UC Davis physicists.
However, the lecture was generally found to be interesting and intriguing to the expert and the layman alike.
“[The lecture] really laid out quite well the things we don’t understand and the things we half understand and the things we just don’t understand at all,“ said Joe Kiskis, professor of physics at UC Davis.
Audience members without an extensive physics background agreed.
“It was a lecture that was designed for people that aren’t professional theorists,” said Ron Glick, a high school teacher in Woodland. “He kind of lost me at the end, but I think it was worth coming out; I’m glad I came.“
Dick Dowell, Davis resident, was intrigued by Gross‘ lecture.
“The thing that amazed me was that all of this microscopic work seemed to relate to the size of the universe, and that is just flabbergasting to me,” he said. “Somehow it all comes together.“
Gross concluded his lecture by commenting on the future of theoretical physics, and how far science has come.
“We’re trying to answer nature’s questions, and that is an enormous stimulus to science and new technology,” the laureate said. “Exciting new discoveries are around the corner and the best is yet to come.“
MICHAEL MILLER can be reached at features@theaggie.org.
