The CU community is one step closer to understanding complex scientific theories after a visit from Brian Green, a well-known physicist.
Greene, a physicist and author of “The Elegant Universe,” was warmly greeted by a packed auditorium at Macky on Wednesday. Opening with gracious statements that reflected his humor and humility, Greene was well received by the Boulder community and the student body.
Greene is known both for his contributions to the world of science, and his ability to simplify very complex theories and synthesis information and mathematical equations so that an average person can understand at least the basics of his theory.
In his opening remark, Greene described the “unrelenting passion to try to find the answer” that has driven generations of scientists to dedicate their lives to the pursuit of a unified theory.
How did the universe become the universe, and what happened at time zero? These are the questions that Greene presented to the audience before offering his theory.
The string theory that Greene spent the better part of an hour explaining to the audience is a popular, yet controversial theory because it has not been empirically proven. Greene explained the string theory in non-scientific terminology, but also gave contextual support for the theory and constructed a historical argument for its validity.
According to Greene, in order to understand what happened at time zero, humanity must establish a unified theory about the deepest laws of the universe.
Greene argued that, “the string theory is the key to the unified theory that Einstein was working on.”
Greene grounded his work with string theory in the resolution of a conflict. Albert Einstein proposed a theory that is in conflict with another theory, quantum mechanics and that conflict prevents the evolution of scientific inquiry into the origin of the universe.
Greene began his lecture on string theory with the story of Einstein and the creation of his theory of general relativity. Greene said that Einstein asked, “What is the mechanism through which gravity operates?”
According to Greene, Einstein challenged accepted knowledge and reevaluated issues that had been perceived to be closed by the rest of the scientific community. In so doing, Einstein developed the general theory of relativity.
Greene explained that the general Theory of Relativity states that the sun, by virtue of its presence within space, affects the shape of space itself. The earth exists in the curved valley that the sun created, and the fabric of space takes on the curved shape of the moon, which exists in the curved environment that the earth created.
Greene kept the audience interested in this complex theory with periodic interjections of humor, often breaking the intensity of the atmosphere in Macky with laughter. So dense was the silent anticipation of the audience that Green once said “bless you” to man sitting in the farthest row of a balcony; Greene could actually hear him sneeze that far away.
Einstein’s theory was brilliant yet flawed, for it contradicted another theory.
“It solved one problem only to open a whole ‘nother can of worms,” Greene said.
Quantum mechanics, as Greene explained, is an experimentally confirmed theory, although it is a rare occurrence that experiment is successful.
Quantum mechanics examines the universe on a microscopic scale, at the level of electrons. This theory does not view the universe in terms of perfect curves; the quantum mechanics view is that electrons move like a “frenzied, boiling pot of water,” according to Greene.
Greene explained the contradictions of quantum mechanics and general relativity in a language that most people understand, the language of food.
He explained that in New York City there is a Chinese restaurant with a specials Column A and B, and if one orders from Column A, one can’t order from Column B. This is essentially what the principle of uncertainty explains.
Having knowledge about one column prevents you from having knowledge about another.
“The better you know about A, the less you know about B,” Greene said.
This relates to quantum mechanics because one cannot know where an electron is and how fast it is moving. One can have knowledge of A or B, but not both.
“There is an unavoidable element of uncertainty built into the fundamental laws of physics,” Greene said.
The conflict that string theory aims to resolve is the contradiction between the perfect form of Einstein’s universe and the chaotic uncertainty of quantum mechanics.
“The jittery, turbulent picture of the universe is in conflict with Einstein… Einstein’s theory breaks down if you try to push his ideas to that microscopic level,” Greene said. “The big and the small don’t fit together.”
Greene began his discussion of the string theory by comforting the audience.
“It’s pretty straightforward,” Greene said.
Greene used visual aids and metaphors throughout his lecture to explain the intricate and extremely complicated details of string theory.
“String theory suggests that there is one more layer, beyond the level of the electron,” Greene began.
String theorists believe there is a filament of elements within an electron that look like a string and can vibrate. The strings vibrate in different patterns, and these patterns govern what that element becomes. Different kinds of particles correspond to different string vibrations.
“A string vibrates in A-sharp and it is an electron,” Greene said. “But the strings are fantastically small…a tree is to the universe what a string is to an atom.”
Because of the size and delicate nature of these strings, Greene stressed that this theory is only a suggestion; it has not been tested, although mathematical equations support the existence of strings.
The theory has the ability to meld together general relativity and quantum mechanics. If one spreads the string out, the stretching dilutes the frenzied chaos at the microscopic level of quantum mechanics to better match the level of general relativity.
String theory suggests that humans are “vibrating to the cosmic symphony of tiny strings,” Greene said.
That may have been what the Beach Boys meant when they sang about “Good Vibrations” in 1979.
But this theory requires that the universe have more than three dimensions, possible nine or 10. String theorists believe that the universe has curled-up dimensions that are invisible to the naked eye, and these dimensions make up a potion of the fabric of space.
“There are many universes out there,” Greene said.
Greene explained that the possibility of other dimensions correlated to the possibility of other universes.
“There is a cosmic bubble bath of universes and we live in one bubble,” Greene said.
Greene concluded his lecture by explaining the possibility of a machine in Sweden, a particle accelerator, to speed electrons up to the speed of light and make them collide. The theory is that when these electrons collide at super speeds, some debris will leave the universe. If this happens, scientists will be able to calculate the energy before and after the collision, and determine, for certain, whether something did leave our universe and go into another.
Greene’s lecture was brought to a close with a furious applause, and an inaudible and innumerable symphony of tiny strings was possibly vibrating energetically as well.
Reactions to this lecture were mostly positive, though some people expressed a certain amount of apathy to the concept of infinitesimally small particles and parallel universes.
“I still don’t care,” said Sarah Rosenbloom, a senior civil engineering major.
Other students and community members said they were impressed with Greene’s straightforward and clear explanation of a complicated theory.
“He did a good job of emphasizing that it is a theory and hasn’t been proven, though it is mathematically possible,” said Eric Tomassini, a junior physics major.
Other students said they found Greene’s humor a helpful way of understanding complicated information.
“He was very funny and he made the information very accessible,” said Abby Simon, a recently graduated environmental studies major. “He did a good job presenting the contextual importance.”
Greene’s best selling point with the audience was the unique way he presented a new and radical theory about the universe in layman’s terms.
“It’s cool that something so on the forefront of science and so uncertain can be presented in such concrete terms,” said Vic Jannatpour, a community member who attended the lecture. “He was very accessible.”
Contact CU Independent Staff Writer Allison Doyle at Allison.doyle@colorado.edu.