April 06, 2006
Roll Over, Einstein:
"Strings" May Reveal Origins of Universe, Physicist Declares at St.
Sure, Albert Einstein offered revolutionary ideas to help lesser
mortals grasp how the universe works.
But even Einstein fell short of the prize scientists have sought
for centuries - namely, an elegant, convincing theory for the
origins of reality itself.
"The big issues haven’t been fully addressed by any means,"
declared renowned physicist Brian Greene on Monday, April 3, before
an audience of nearly 200 students, alumni and faculty at St.
"Though Einstein undeniably had a dramatic impact on the way we
think about things," he added, "one goal eluded him
- finding a ‘unified theory’ of the universe."
Today, Dr. Greene said, that theory may be closer than
ever, thanks to a mysterious substance physicists call "strings" -
tiny particles of vibrating energy. Their worm-like wriggling in
the fabric of reality may be the key to questions that stumped
Einstein, Newton and other giants of physics.
"These are lofty questions," Dr. Greene noted. "What is space?
What is time? What are the basic ‘entities’ that make up the
‘stuff’ in the world around us? And what are the laws by which
those entities . . . drive the evolution of the cosmos?"
A "Cutting-Edge" Idea
Combining video clips, a disarming sense of humility and frequent
bursts of humor, Dr. Greene held the audience as he explored these
issues in "Explaining the Elegant Universe," the lecture he
delivered in Marillac Auditorium on St. John’s Queens campus.
The presentation was part of a new lecture series sponsored by
St. John’s College of Liberal Arts and Sciences.
A professor of physics and mathematics at Columbia University,
Dr. Greene is one of the world’s leading proponents of "Superstring
Theory" - an attempt to find the "Theory of Everything" that eluded
"You have to bear in mind," he said, "that this is not a
‘theory’ in a traditional sense. These are cutting edge ideas, not
yet tested by the experimental community."
What are superstrings? They are, Dr. Greene proposed, the tiny
particles we would find if we could slice open electrons or quarks.
These "infinitesimally small filaments" vibrate "like the strings
of a violin or cello." The vibrations create something far
different from sound.
"Strings do not produce music," Dr. Green explained. "They
produce particles. When a ‘string’ vibrates in one pattern, it
forms an electron. When it vibrates in another pattern, it forms a
Dr. Greene readily admitted that no one has ever observed
superstrings. "They’re too darned small," he said. But, he added,
the concept is "sufficiently rich and compelling that it’s worth
the journey, worth thinking about them and reaching some conclusion
in the not-too-distant future."
Dr. Greene based the lecture on his New York Times-bestselling
book, "The Elegant Universe: Superstrings, Hidden Dimensions, and
the Quest for the Ultimate Theory" (1999). A Pulitzer-Prize
finalist and winner of the Aventis Prize for Science Books, "The
Elegant Universe" became a PBS television special that Dr. Greene
narrated. Another book, "The Fabric of the Cosmos" (2004), also was
a New York Times bestseller.
Attesting to Dr. Greene’s popularity with the general public,
his St. John’s lecture attracted people of all ages - even
children. During a lively question-and-answer session after the
lecture, one boy eagerly waved his hand until Dr. Greene pointed to
him. "How did the Big Bang get there out of nothing?" the boy
Without missing a beat, Dr. Greene smiled and said, "I don’t
know - nobody does. At Columbia, I direct the Institute for String,
Cosmology and Astroparticle Physics. We’re trying to put String
Theory and cosmology together to hopefully answer your question, to
figure out what the nothingness is and how the 'somethingness' we
know today emerged from it."
Though the concept of "super strings" is far from a "proven
theory," said Dr. Greene said, many physicists believe it can lead
to the unified theory that Einstein so passionately
A "Theory of Everything"
To explain, Dr. Green showed a film clip with an animated
representation of the Big Bang - the mammoth explosion physicists
say created the known universe.
"The universe came into existence as a very small, very dense
entity," he said. "Then it went through an explosion, in which
matter, space and time were thrown outward. As everything got
bigger, it cooled. Structures congealed out of the primordial
plasma... the stars and galaxies we see today."
"Here’s the thing," he said. "We can make use of the known laws
of physics to turn this film back to a fraction of a second after
the beginning. But if we try to go any further back, the laws of
physics break down, giving us noise, static - a complete lack of
understanding at what happened at time zero itself."
The reason is reality’s increasingly bizarre behavior as objects
become smaller. Ordinary physical laws no longer apply to objects
as small as scientists believe the universe was before the Big
Bang. To understand what happened, scientists need a "theory
of everything" to unify two seemingly conflicting theories of
The first, said Dr. Greene, is Einstein’s "Special Theory of
Relativity," a mathematically precise explanation for "the
beautiful, geometric way" that gravity affects how objects move in
the observable universe. The second is quantum mechanics, which
physicists developed in the 1920s and 1930s to explain the very
different behavior of atoms, molecules and sub-atomic
"The older theories - including Einstein’s - gave wrong
predictions for what was being observed on the smallest scales,"
said Dr. Greene. "This alerted a generation of scientists that they
needed to develop laws for the micro-world. Quantum mechanics is
what they came up with."
This new theory depicts a "micro reality" seemingly at odds with
the more orderly reality described by Einstein and earlier
theorists. For example, conventional theories maintain that objects
like electrons can never penetrate an apparently solid barrier.
"Quantum mechanics says it can," said Dr. Greene. "The experiments
found that every so often, electrons shot at a barrier will
The Big, the Small and
Unlike the seemingly predictable "big" universe, the "micro-world"
follows principles strangely at odds with observed reality. In
experiments with particles, said Dr. Greene, scientists who plot an
electron’s location suddenly are unable to calculate its speed.
Likewise, calculating an electron’s speed seems to interfere with
calculating its location.
Dr. Greene referred to a mealtime dilemma familiar to many New
Yorkers. "Since we’re in the vicinity of Chinatown," he said,
"let’s use the analogy of a special order menu. You have Column ‘A’
and Column ‘B.’ If you order a dish from Column ‘A,’ the manager
will say you can’t order a corresponding dish from the other
"That," he continued, "is the principle in microscopic realm.
The more you know about an element from the first list, the more
that knowledge fundamentally compromises your ability to understand
features from the corresponding list."
In other words, he said, "the more you know about an electron’s
position, the less you can know about its speed; the more you know
about its speed, the less you can know of its position."
"Due to quantum uncertainty, there is a fundamental limit to
what we can know." Though this is especially true on the
micro-level, Dr. Greene added, uncertainty does exist in the
observable universe, but its effects decrease as we enlarge our
Resolving the Conflict
To understand the Big Bang, and what came before it, scientists
must reconcile the different physical laws governing the big and
small. "Superstring Theory" appears to do just that.
"I think we are not merely trying to model the universe," said
Dr. Greene. "We are trying to figure out the truth about how it
works. If there’s a clash in theories about the universe -- a point
where known laws break down -- then there must be a deeper story to
Identifying "the finest entities making up matter," said Dr.
Greene, is the place to start. Conventional theories hold that the
smallest particles of matter are quarks - "tiny dots with nothing
"String theory challenges that," he said. "Inside those quarks,
those tiny dots, is something finer: a tiny filament of string-like
energy that vibrates in different patterns, like strings on a
cello." The ways the filaments vibrate create the next smallest
level of particles, like quarks, electrons and protons.
Moreover, said Dr. Green, the shape of the tiniest particles can
build bridge the gulf between relativity and quantum mechanics.
"How does it unify the laws of big and small?" said Dr. Greene.
"When you have a string rather than a dot as the smallest particle,
you spread it out. When you spread something out, you dilute it,
the way ink dilutes as it spreads out in water."
This "spreading out" can explain why physical laws at the
smallest levels of reality are so volatile - "jittery," in Dr.
Greene’s words - while the larger-scale, observable universe seems
more orderly. "Spreading out particles dilutes the ‘jitters’ in
space," he said. "It becomes less severe." The more volatile
physical reality of the smallest reality can reach "the right
intensity" to fit the larger scale universe.
According to Dr. Greene, the theory also can explain a more
esoteric aspect of reality. To hold together, the mathematics of
string theory requires ten dimensions rather than three. The
existence of ten dimensions - "curled up" realities presumably two
small for human beings to observe - might explain another discovery
that physicists have made.
"Over the last 100 years," said Dr. Greene, "physicists and
other scientists have measured the features" that seem to make up
reality. As a result, they have identified "twenty key numbers,
encapsulating such features as the mass of electrons, the strength
"No one knows why the numbers have the precise values they do,"
he continued. "But if we were to change any of those numbers by
even a small percent, the universe as we know it would go away.
Fiddle with the value of those numbers, and nuclear processes could
not happen, and stars would not light up."
The concept of ten dimensions, said Dr. Greene, could explain
why those critical numbers possess the values they do. The shape of
the dimensions - "complex manifolds, with a rich geometry" - could
influence the vibrations of strings "just as the shape of a French
horn influences the sound patterns" produced by breath moving
through the instrument’s valves.
Just the Beginning
After the lecture, Dr. Greene made time to autograph copies of his
books and to pose for photographs with admirers. Before breaking
for a special reception, however, he answered a barrage of audience
questions - including one from Dr. Jeffrey Fagen, Dean of St.
John’s College of Liberal Arts and Sciences.
"If ‘String Theory’ does prove to be true," asked Dean Fagen,
"will I still need a physics department?"
Laughing, Dr. Greene assured the audience that finding a "Theory of
Everything" would not end the quest for learning more about the
"To my mind," he said, "this is a beginning, not an end. We’re
trying to figure out the rules of the universe... when we have
those rules, that’s where the fun begins. So yes, I still think
you’ll need a physics department."
This lecture by one of the world’s leading physicists offers a
striking example of the intellectual discourse available to
students, faculty and alumni of St. John’s University. We invite
you to relive the excitement of the event by viewing our Photo