Kip Thorne's got chalk skills. serious chalk
skills.
At the moment, he's blanketing a blackboard with equations
so densely packed with Greek letters, mathematical symbols and
superscripts that they look more like abstract art than any recognizable
form of human discourse. To the nonscientist, the scene has the
theatrical, you've-got-to-be-kidding-me feel of an outtake from "A
Beautiful Mind"—the manic scientist cranking out arcane formulas while
onlookers gaze in wonder.
But this isn't a Hollywood set. It's a
lounge on the campus of Caltech, where Thorne is the Feynman Professor of
Theoretical Physics and just about every room, restrooms excepted, is
furnished with a blackboard. This particular Wednesday evening, the lounge
is packed with nearly two dozen graduate students, doctoral candidates and
postdocs. Several are members of the research group Thorne runs with
fellow professor Lee Lindblom. But most of them are sitting in on the
group's weekly meeting simply because they've heard that Thorne is going
to be "posing some interesting problems." And they smile when he says, "I
had some time on my hands so I thought I'd think about
physics."
Thirty-two years ago, when Thorne became one of the
youngest full professors in the history of the California Institute of
Technology, he was a longhair partial to funky pendants and bell bottoms.
Today, as an éminence grise in black-hole research and
gravitational-wave studies—fields he helped create—he looks like a cross
between Santa Claus and a tortured El Greco saint, with a mane of flowing
hair and a white beard framing attenuated features, a gaunt face and ruddy
complexion. At 62, he's slightly hunched, and he has a vocal tic similar
to a hiccup. Yet his students regard him with the respect that martial
arts students bestow upon their senseis.
They nod knowingly
when he explains, "I'm not concerned about delta H over H. I'm interested
in delta H over G, where G is a typical metric coefficient." They listen
attentively as he delivers a characteristically gentle rebuke: "I think
you might want to look more closely at the problem. It's not just the
spin-supplementary condition. It's also radiation-reaction averaging."
They jot down notes when he asks them, "So how do we get past the
standing-wave problem to the real problem? That's the question I want to
raise as LIGO comes online."
Thorne is a co-founder of the Laser
Interferometer Gravitational-Wave Observatory. Big name, big mission: LIGO
is designed to detect ripple-like disturbances in the theoretical "fabric"
of space and time known as gravitational waves, whose existence was first
posited by Albert Einstein in 1916 but which have yet to be observed
despite decades of searching. Detecting this great white whale of
black-hole physics would verify the underpinnings of Einstein's general
theory of relativity. Also, the waves are expected to contain information
that would unlock the mysteries of black holes and give us a dramatic new
window on the secrets of the universe.
Time out for a quick physics
primer: Einstein's theories of relativity hold that space and time
are—yep, you got it—relative rather than absolute. According to Einstein,
the universe is best thought of in terms of a four-dimensional fabric
known as spacetime. Gravity can cause this fabric to warp, contort,
oscillate and basically do anything short of the lambada. But nowhere does
spacetime undergo stranger, stronger distortions than in and around the
stellar phenomena known as black holes—dead stars that have collapsed to
form masses so dense their gravitational pull prevents even light from
escaping, therefore rendering them invisible.
Black holes are
ciphers by definition; we infer their existence from the powerful effect
they have on the space around them. But while they emit no light, radio
waves or X-rays, they do send out waves made of the same stuff as
the holes themselves—warped spacetime. These so-called gravitational waves
are undulations in the fabric of space-time, like the ripples caused by
dropping a stone in a pond. The biggest waves are produced by the most
cataclysmic events—a supernova, say, or the collision of two black holes.
These waves contain the story of their own creation, and we could play
them back like high-fidelity tapes—if only we could detect them.
"I
and many other relativity theorists have spent much of our lives working
with the mathematics of general relativity, trying to understand what it
predicts—for example, predictions it makes about black holes," Thorne
says. "But we have almost no experimental data to support these
predictions. And when we get to the most interesting situations—where
space and time are oscillating, twisting, vibrating, distorting—we don't
know how to solve the equations. Gravitational waves will allow us to
watch space-time distort rapidly, in large magnitudes. Then we can
go back and forth between theory and observation to finally figure out how
everything hangs together."
Like a brainy, genial Ahab, Thorne has
been chasing gravitational waves for nearly a quarter-century. Thanks
largely to his tireless efforts, two enormous observatories have been
built, one in Louisiana and another 2,000 miles away in Washington state.
Housed within these odd structures are devices called interferometers that
are designed to detect gravitational waves by measuring movements of
almost incomprehensible smallness.
Now, with the first scientific
data runs just weeks away, Thorne is about to see his lifelong vision come
into focus. Even so, he suspects that gravitational waves won't be
detected until second-generation interferometers are built. "I wish we
didn't have to do it in two steps," he says. "I wish we hadn't had to
build a $300-million facility to make it happen. I wish we could have done
it on a tabletop. But nature just isn't made that way."
No matter
what LIGO finds—or doesn't find—Thorne's reputation is secure. Oddly
enough, it has less to do with his own scientific achievements than with
creating an environment for others to make award-winning breakthroughs.
He's been an evangelist for black-hole and gravitational-wave physics, not
only luring nonbelievers but also drumming up donations (a.k.a. federal
funding). He's been an effective mediator between traditional scientific
adversaries—theorists and experimentalists, for instance, and astronomers
and physicists. But most important, he has inspired young scientists to
follow his example and imprinted them with his own qualities. Equal parts
Mr. Chips and Mr. Wizard, Thorne is the Pied Piper of theoretical
physics.
"He's a fantastic mentor. There is a whole cabal of former
students who still admire him very, very much," says Clifford Will,
chairman of the physics department at Washington University in St. Louis.
"Not only did he motivate us to become better scientists, but he also
inspired us to be better listeners and teachers." Adds another former
student, Richard Price, now a professor of physics at the University of
Utah: "Kip was one of the first scientists to take general relativity,
which most people saw as an intellectual curio, and apply it to
astrophysics. But more than any single theoretical breakthrough, he will
be remembered for populating this new field with students. He taught them
how to behave—morally, ethically and scientifically."
Thorne is the
co-author of one of the only science textbooks long-lived enough to
justify being called a classic. (Pirated editions of "Gravitation" are
still being printed in Kurdistan 30 years after the book's initial
publication.) At the other end of the spectrum, he also wrote the
pop-science bestseller "Black Holes & Time Warps: Einstein's
Outrageous Legacy," which, along with more serious subjects, detailed his
blueprint for a time machine and prompted Caltech President David
Baltimore to dub him "Caltech's number-one strange scientist, the prince
of counterintuitive science."
Some of Thorne's friends wonder if he
might have achieved more personally if he had spent more time on his own
research and less on mentoring his charges. But Thorne waves this notion
aside. "I feel I've had a deep influence on science through my students,"
he says. "If you take a look at what my students have done while they were
students, forgetting about what they've done afterward, you'll find that
they've collectively accomplished more than I could have done on my
own."
LIGO is Big Science. capital b, capital s. To date, $365
million has beenspent on two separate facilities in Hanford, Wash., and
Livingston, La. An additional $165 million has already been committed over
the next five years to upgrade to second-generation interferometers. This
makes LIGO the most ambitious project ever funded by the National Science
Foundation.
The LIGO facilities look every bit as strange as the
gravitational waves they were built to detect. In aerial photographs, they
look like giant crop circles left behind by inscrutable aliens. Splayed
out at right angles to the angular central structure are two spindly legs
that resemble giant pipelines leading to nowhere. Encased within each one
of these long half-cylinders—picture Quonset huts 2 1/2 miles long—is a
4-foot-diameter vacuum tube. A mirror dangles from a wire at the end of
each leg. When the interferometer is running, a steadily shining laser
beam in the central structure is split in two. These beams shoot down the
two tubes, bounce off the dangling mirrors and return to the center. There
they merge and "interfere" with each other.
Here's where things get
tricky. Astrophysicists say gravitational waves are constantly wafting
across the universe, causing space to stretch along one axis and squeeze
along the other. This distortion is so minuscule that we don't ever notice
it. (Ditto, fortunately, for nearly all of the most dramatic effects of
general relativity.) The problem, of course, is that it's also too small
for scientists to detect.
Enter the interferometer. When an
especially powerful gravitational wave from a distant universe passes over
a LIGO site, the space around one leg ought to shrink while the space
around the other stretches. This should cause the mirrors within to quiver
ever so slightly. Less than slightly, actually. Infinitesimally
hardly begins to describe it. LIGO director Barry Barish pegs the
movement at 10 to the minus-18th meters, or ten billionth's the diameter
of a hydrogen atom.
Still, this would be enough to nudge the two
returning laser beams out of phase, causing their interference to change.
This modified interference should reveal the shape, or form, of the
passing gravitational wave in much the same way that sound can be charted
on an oscilloscope. (Besides mounting the interferometers on exotic shock
absorbers, the scientists built two LIGO facilities in different
parts of the country to rule out seismic vibration or other so-called
noise as the cause of any observed movement.)
"If and when LIGO
detects gravitational waves, it'll be a big deal," Thorne says. "But our
goal has never been detection alone. It's been to use these waves to
explore aspects of the universe and fundamental physics that we can't
explore any other way. We want to be able to make maps of the warpage of
space-time. We want to see how warped space-time behaves when two black
holes collide. We should be able to see things unlike anything we've seen
before."
For virtually all of human existence, our knowledge of the
cosmos has been limited to what we could observe with our own eyes, either
unaided or through optical telescopes. But the 1940s brought the
development of radio telescopes and, soon after, other alternative
observational devices that expanded the distances we could see and gave us
our first glimpse of phenomena such as pulsars and quasars. Despite these
advances, our vision is still limited to objects that emit electromagnetic
waves—light waves, gamma rays, X-rays and so on. This accounts for only a
puny slice of the universe. Gravitational waves, on the other hand, should
allow us to observe black holes and other matter that remains shrouded
from our sight.
Astrophysicists have already produced reasonably
firm evidence of gravitational waves. In 1993, the Nobel Prize for physics
was awarded in part for this discovery. But the waves themselves remain
elusive. And if it turns out that they don't exist, then there's a serious
problem with the concept of relativity.
In 1905 and 1916, Albert
Einstein published his special and general theories of relativity. With
these two papers, he demolished the foundations of Newtonian physics and
reimagined our universe. By 1919, with the publication of proof that an
extremely large mass, in this case our sun, caused light to bend, general
relativity was confirmed and Einstein was hailed as a genius. But for
several decades, some of the more implausible implications of general
relativity—the existence of gravitational waves, for example—were ignored
or dismissed as mathematical oddities.
Before physicists could
tackle gravitational waves, first they had to puzzle out black holes. But
because astronomers couldn't see them, black holes were regarded with
skepticism, if not outright derision, until the late 1950s.
By
happy coincidence, this was when student Kip Thorne arrived at Caltech, a
scientist both by nature and nurture. He is the eldest child of two
academics: His father was a professor of soil chemistry at Utah State
University, where his mother later founded the women's studies program.
(Two of his four siblings are professors.) His interest in science was
fired at age 8, at a lecture about the solar system. "My mother and I
worked out calculations for building our own model of the solar system,"
he recalls. "The model consisted of drawing a 4-foot-diameter sun on the
sidewalk near our house. Then we drew all the planets to scale [and]
marched down the sidewalk to put them in the right place. The shock was
finding that Pluto was in the next town!"
After earning an
undergraduate degree from Caltech, he pursued his doctorate at Princeton
University under relativist John Wheeler. Besides being a titan of
mid-century physics, Wheeler was an inspirational mentor. Teacher and
pupil were well matched, and they became two of the architects of a heady
period known as the golden age of black-hole research. During this
remarkable period, between the early 1960s and the mid-1970s, Wheeler
coined the term black hole and the first such object—Cygnus X-1—was
identified. Meanwhile, Thorne returned to Caltech to teach and put
together his own ambitious, impassioned research group.
"I called
it the Children's Crusade of general relativity," says William Press, a
student of Thorne and Wheeler who's now deputy director of science and
technology at the Los Alamos National Laboratory in New Mexico. "Except
for John Wheeler, almost everybody in the field was very young, and it was
a period of endless promise. At Caltech, if you were interested in general
relativity, you studied with Kip. He couldn't take on enough graduate
students."
But by 1975, after a decade of spectacular progress,
theoretical physicists ran up against an experimental roadblock. As Thorne
puts it: "We had pretty much done all we could do in terms of mathematical
solutions or approximation techniques, and the only way to make major
progress was either through computer simulations or through observations,
or both. Only now, in 2002, thanks to supercomputers and LIGO, are we on
the verge of both approaches coming to fruition. But there's been a long
period of building the right tools."
One November night in 1976,
Thorne wandered the streets of South Pasadena, seeking direction. "I was
sure that if we were successful in detecting gravitational waves, it would
have a profound impact on our understanding of black holes and the
universe," he says. "But the waves are so weak and the task of detecting
them was so daunting that I wasn't sure the odds of success were high
enough that I should urge Caltech to get involved in the
business."
In the end, he decided that the potential reward
outweighed the risk. He subsequently became part of a triumvirate with two
experimentalists—Rainer Weiss of MIT, who invented the gravity-wave
interferometer, and Ron Drever of Caltech, who refined it—and set about
trying to sell the program to the National Science Foundation, the federal
agency created to support blue-sky research on the frontier of pure
science. Twice they failed. In 1989, on their third try, with former
Caltech provost Robbie Vogt as LIGO director, they finally came up with a
winning plan. Even then, they had to run a five-year gantlet of reviews
before getting the foundation's ultimate go-ahead in 1994.
These
days, Thorne and his students are designing second- and third-generation
interferometers. He's also organizing a Caltech supercomputer effort to
simulate colliding black holes and other cosmic cataclysms. He
stresses—forcefully and repeatedly—that he's not involved with the
day-to-day operation of LIGO, and he insists that the bulk of the credit
for the program belongs to the experimentalists who built and run the
interferometers. "I'm just a theorist," he says, "and I'm quite concerned
that my role not be overplayed."
Thorne's colleagues chuckle when
they hear this assessment. "That sounds just like Kip," says Sandor
Kovacs, a former student-turned-physician who teaches at the Washington
University School of Medicine. No less an authority than Thorne's longtime
friend Stephen Hawking has said, "I don't think [LIGO] would have happened
if he hadn't pushed it so hard."
This thought is echoed by Vladimir
Braginsky of Moscow State University, who's been working with Thorne since
long before the end of the Cold War. "LIGO could not have gone forward
without Kip Thorne. It will be his legacy. This project will live in the
memory of mankind for centuries."
In his narrow, nondescript office
at Caltech, Thorne grabs an old notebook from a bulging bookcase and opens
it at random to a page filled with meticulously neat, handwritten formulas
not unlike the ones he'd scrawled across the blackboard at the weekly
meeting of his research group a few days earlier. These are his own notes,
taken when he was a student struggling to keep up with the ferocious
competition.
"When I arrived at Caltech, I took a bus to the
freshman orientation camp," he recalls. "On the way, all the kids were
quoting their IQs, and mine was 10 points below everybody else's. I had a
pretty rough time keeping up that first year. So I started identifying the
important ideas that were being taught and writing my own analyses of
where they came from and how they related to each other. So instead of
having textbooks with some underlining as my major source of information,
I had my own summaries. I think this process enabled me to understand
things more deeply than other people and allowed me to make connections
that they didn't see."
These days, Thorne does most of his serious
thinking at a getaway on the wild Oregon coast and in the north Pasadena
home he shares with his second wife, Carolee Winstein, a professor of
biokinesiolgy and physical therapy at USC. (Thorne has two grown children
from a previous marriage.) His office was designed by his son, an
architect. It's filled with exquisite woodworking crafted by his brother,
who builds artisanal furniture. In this airy room ringed with windows, he
pores over calculations for four or five hours at a stretch—a grinder, he
insists, who succeeds by doggedness rather than
genius.
Self-effacing to a fault, Thorne waffled mightily when he
was offered the Feynman chair at Caltech. "Feynman was a
close friend, somebody I admired and idolized," he says. "But it was
difficult because I'm obviously not in his class scientifically. Of
course, not many people are." Thorne laughs. "My genius, if you can call
it that, has been picking areas where there was a lot of elbow room and
something to be learned, and I've carefully avoided areas where there was
a lot of activity by a lot of good theorists."
In one field,
actually, Thorne has emerged—much to his amusement—as the world's most
celebrated thinker. His friend Carl Sagan once asked him to vet the
time-travel section of the manuscript that would eventually be published
as "Contact" and then filmed as a movie starring Jodie Foster. Thorne
immediately dismissed Sagan's hypothesis. But while driving on the I-5,
west of Fresno, he had an epiphany: It might be possible to use a
wormhole—a shortcut through the fabric of space-time—as a time
machine.
Most scientists would have dismissed such speculation as
pointless. Not only was the subject highly speculative, but it also
carried the whiff of ridicule. Nevertheless, Thorne examined it with the
same rigor he applies to any other subject, and he and two students
published a paper titled "Wormholes, Time Machines, and the Weak Energy
Condition." To this day, Thorne remains a hero to science-fiction cultists
because of that and other papers.
Thorne's own
hero, of course, is Einstein, the patron saint of relativity. And so, this
afternoon, before teaching his own class in gravitational waves, he is
himself a student at a Caltech lecture being given by one of his former
pupils. The subject is "Einstein and the Astronomers: Testing Relativity
1914—1933." Forty professors, researchers, administrators and students
listen while Daniel Kennefick, dressed incongruously in shorts, traces the
journey by which Einstein arrived at his general theory of
relativity.
In the middle of the presentation, a research scientist
challenges the figure Kennefick has cited for an orbital anomaly of
Mercury—an anomaly that baffled astronomers until Einstein explained
it.
"Kip?" Kennefick asks hopefully of his one-time graduate
advisor. Thorne digs into his briefcase and pulls out a pen. While the
lecture continues, he scribbles calculations on a manila folder. Then he
announces: "It's 43 seconds of arcs per century, not 0.43."
After
the lecture, Thorne deconstructs his parlor trick in a way that would make
sense to precious few people on the planet: "Well, I knew in order of
magnitude that the size of the sun divided by the size it would have if it
were a black hole is about 100,000. So the typical magnitudes of
relativistic effects near the surface of the sun are about a part in
100,000. Mercury's orbit is out maybe something like 30 solar radii from
the sun. So relativistic effect on Mercury's orbit ought to be a factor of
30 times smaller, or about 3 parts in 10 million. So the perihelion shift
per orbit ought to be about 3 parts in million of a circuit. Then I just
had to convert this into an angular shift per century." Thorne smiles
sheepishly. "I should have known the number off the top of my head, but my
memory is lousy."
As he strides across the campus to his own
lecture hall, Thorne pauses to chat briefly with an old man sitting on a
bench. "That was Jerry Wasserburg," he explains later. "He showed that the
solar system is 4.58 billion years old. He won the [equivalent of] the
Nobel Prize for geology. He's a wonderful man, approaching 80 now but
still doing wonderful research."
Twenty years from now, chances are
somebody will be saying the same thing about Kip Thorne.
Preston
Lerner last wrote for the magazine about car designer Freeman Thomas.








