Testing Einstein's Theory: Relativity Project Has Stretched Over Four Decades
from LA Times reprinted

Palo Alto, Calif. -- In 1962, Francis Everitt, a restless young physics researcher from England, signed up at Stanford University for what he thought would be a "few years of entertaining work" on a space project.

The goal was to put a satellite in orbit 400 miles above Earth to validate or disprove, once and for all, Albert Einstein's general theory of relativity.

Four decades and $700 million later, Everitt is still working on Gravity Probe B.

In the meantime, NASA has landed men on the moon, built the international space station and sent probes to Mars. Two of the three Stanford professors who came up with the idea for the gravity probe while skinny-dipping at the campus pool in 1959 have died.

"They were telling me about this far-out idea, and I thought I would work on it for a few years before going back to England," said Everitt, now 69 and an Einstein look-alike with his mustache and graying, frizzy hair. "I didn't realize how far out it was going to be."

Gravity Probe B, about the size of a van, was originally expected to lift off into space in 1975 at a cost of about $35 million. NASA has pulled the plug on the project seven times over the years. Each time, it was resurrected, thanks to Everitt's unrelenting lobbying of Congress.

[...]

Under Einstein's theory, Earth, like a bowling ball thrown on a rubber sheet, stretches the invisible fabric of space and causes smaller objects to move toward it. As Earth rotates, it churns the fabric, dragging space and time around it like a pinwheel.

The physicists who dreamed up Gravity Probe B hoped to test Einstein's theory with a spinning gyroscope encased in a spacecraft orbiting in near-zero gravity. The device would respond to Einstein's predicted warping of space and time -- or, perhaps, would not.

The experiment was also designed to detect the effect known as "frame dragging." If Einstein was right, the orientation of the spinning 1½-inch gyroscope would tilt slightly over time in response to Earth's gravitational force. If the gyroscope did not tilt, or tilted less than predicted, Einstein's theory would come under rigorous new scrutiny.

Supporters, including several Nobel laureates, say the mission is essential to understanding one of the fundamentals of modern physics -- how gravity shapes space and time.

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Testing Einstein's Theory
Relativity Project Has Stretched Over Four Decades
By Peter Pae
Los Angeles Times

Palo Alto, Calif. -- In 1962, Francis Everitt, a restless young physics researcher from England, signed up at Stanford University for what he thought would be a "few years of entertaining work" on a space project.

The goal was to put a satellite in orbit 400 miles above Earth to validate or disprove, once and for all, Albert Einstein's general theory of relativity.

Four decades and $700 million later, Everitt is still working on Gravity Probe B.

In the meantime, NASA has landed men on the moon, built the international space station and sent probes to Mars. Two of the three Stanford professors who came up with the idea for the gravity probe while skinny-dipping at the campus pool in 1959 have died.

"They were telling me about this far-out idea, and I thought I would work on it for a few years before going back to England," said Everitt, now 69 and an Einstein look-alike with his mustache and graying, frizzy hair. "I didn't realize how far out it was going to be."

Gravity Probe B, about the size of a van, was originally expected to lift off into space in 1975 at a cost of about $35 million. NASA has pulled the plug on the project seven times over the years. Each time, it was resurrected, thanks to Everitt's unrelenting lobbying of Congress.

More than 400 physicists, 2,100 engineers and countless Stanford students have worked on the project. Nearly 100 professors earned their doctorates developing, evaluating, analyzing and building it. Research papers on the probe fill entire sections of Stanford's engineering and physics libraries.

Stanford even built a three-story building for the project, the only facility on campus dedicated to a single mission. Today, about 55 full-time staffers work on the probe, with more than 100 students, visiting scholars and engineers involved at any given time.

For 42 years, Everitt has worked on nothing else. A tenured professor of physics at Stanford, he has never taught a class.

But he has been busy. As principal investigator for the gravity probe, he has written or co-written more than 100 research papers on the project. He also helped develop groundbreaking technologies that will be key to the probe's success -- if it ever makes it into space.

Though the project has produced some dazzling, technologically advanced instruments and could yield enormous benefits for physics, it arguably has had more delays, cost overruns and cancellations than any other NASA scientific endeavor.

"There has been nothing like it in NASA's history," said Rex Geveden, deputy director of NASA's Marshall Space Flight Center in Huntsville, Ala., who has overseen the project for nearly a decade. "It's hard to believe that the idea came about at the dawn of the Space Age."

In December, Everitt and his team came tantalizingly close to launching the trumpet-nosed satellite from Vandenberg Air Force Base in California after half a dozen attempts over the years. But a technical glitch prompted NASA to postpone the launch once again, this time until April, while the probe undergoes repairs.
The Long Wait

"We've waited 40 years. What's another few months?" Everitt said. "It's nothing like what the medieval cathedral builders had to go through."

Einstein's general theory of relativity, published in 1916, said in part that gravity is not an invisible force -- as Newton theorized -- but rather a distortion in the fabric of space caused by massive objects.

Under Einstein's theory, Earth, like a bowling ball thrown on a rubber sheet, stretches the invisible fabric of space and causes smaller objects to move toward it. As Earth rotates, it churns the fabric, dragging space and time around it like a pinwheel.

The physicists who dreamed up Gravity Probe B hoped to test Einstein's theory with a spinning gyroscope encased in a spacecraft orbiting in near-zero gravity. The device would respond to Einstein's predicted warping of space and time -- or, perhaps, would not.

The experiment was also designed to detect the effect known as "frame dragging." If Einstein was right, the orientation of the spinning 1½-inch gyroscope would tilt slightly over time in response to Earth's gravitational force. If the gyroscope did not tilt, or tilted less than predicted, Einstein's theory would come under rigorous new scrutiny.

Supporters, including several Nobel laureates, say the mission is essential to understanding one of the fundamentals of modern physics -- how gravity shapes space and time.

The gravity probe "is our only hope for high-precision test and study of frame dragging," said Kip Thorne, a celebrated physicist at the California Institute of Technology and author of Black Holes and Time Warps: Einstein's Outrageous Legacy.

Whatever the outcome of the experiment, there is little argument that the satellite is a marvel of engineering.

The skinny-dipping professors -- Leonard Schiff, William Fairbank and Robert Cannon -- came up with the idea of using a spinning gyroscope in space to test Einstein's theory. It fell to Everitt and other Stanford physicists and engineers to create the actual hardware. They invented and built much of the technology used in the project, often by trial and error. This painstaking work took decades.
Precise Work

The gyroscope, for instance, is a million times more accurate than any other instrument on Earth at detecting motion and direction. The gravity probe will carry four such gyroscopes: one to test Einstein's theory and three backups.

Inside each one is a sphere the size of a pingpong ball. The sphere is so smooth that if it were the same size as Earth, its highest mountain would be 8 feet tall.

Stanford scientists developed the machine used to make the ball; the device spends months polishing a quartz block into a sphere.

Having made the ball, scientists had to invent a way to suspend it in a casing without any parts touching it. Researchers found they could float the ball in a near-total vacuum by coating it with a superconducting metal and encasing it in a housing lined with electrically charged electrodes. The ball and the electrodes act like repelling magnets.

To create the magnetic effect, the gyroscope must be chilled to within a few degrees of absolute zero, or about minus 460 degrees Fahrenheit. So scientists created a large Thermos of sorts to house and cool the gyroscope in space.

To get the most accurate measurement, the gyroscope's ball has to be spun at high speed. Scientists figured out a way to use tiny jets of helium gas, shot into a space measuring 5/10,000 of an inch, to start the ball spinning. It eventually revs up to 10,000 revolutions per minute.

Then the scientists needed an instrument to detect any shift in the ball's orientation as it spun. The instrument they devised, called the Superconducting Quantum Interference Device, or SQUID, measures changes in the ball's rotation axis by detecting changes in the magnetic field surrounding the sphere.

Any tilt would be so slight that detecting it would be equivalent to discerning Abraham Lincoln's forehead on a penny from 3,600 miles away.

Once the probe was launched, measurements of the gyroscope's behavior would be transmitted to a station at Stanford for analysis.

"It's a very sophisticated experiment, probably the most sophisticated that I have ever seen," said Gerald W. Elverum Jr., a retired executive at TRW Inc. who worked on many of the nation's aerospace programs, including the development of ballistic missiles and the Apollo missions to the moon.

Sometimes, Everitt and his associates had to wait for a technology to develop before they could build a key device. The scientists, for instance, settled on quartz as the material for the gyroscope ball after experimenting with myriad other materials. That step alone took 21 years.

"When this was first proposed, there were at least a dozen technologies that didn't exist," said Brad Parkinson, the project's co-principal investigator, who also helped develop the now-ubiquitous global positioning system.
Multitasking

To develop the tools to build the probe, Everitt became expert in a variety of disciplines, including aerodynamics, chemistry, engineering, mathematics and astronomy. "I can honestly say I've never been bored," he said.

He had to develop a separate set of skills to maintain funding and political support for the probe.

The glacial pace of development made it a target for NASA and congressional budget-cutters and the subject of numerous scientific reviews. Each time, questions were raised about the feasibility of the project. Each time, independent evaluations by panels of the nation's top academics concluded that the mission was worthwhile.

It was tougher convincing NASA, Everitt said. "I never had any idea I would get into the amount of political battling that I got into to keep the program going," he said.

Everitt spent so much time in Washington lobbying to restore funding that he memorized the layout of congressional office buildings.

For the launch scheduled in December, invitations went out to 1,500 people, including many current and former congressional staff members who helped Everitt shepherd the project.

Among those invited was William Fairbank Jr., eldest son of professor Fairbank. He said his father talked about the probe every chance he had.

"He would go to church and talk to them about what he was doing," said Fairbank, a physics professor at Colorado State University. "We would go pick him up at Stanford and we would have to wait 30 minutes to an hour while he talked about his project to someone he ran into. He talked about it during dinners."

Cannon, now in his 70s and a professor emeritus at Stanford, is the only surviving member of the group that thought up the project. He said no one imagined it would take so long.

"It seemed like such a simple idea at the time," he said.

If the satellite is launched in April, the probe will transmit data for 18 months before Everitt's team can confirm whether Einstein was right about gravity.

In the meantime, Everitt has begun another project that he said "could be even more interesting."

Lobbying Congress once again, he has secured $3 million to begin development of a space probe to test Galileo's theory about how objects fall at the same rate of acceleration regardless of weight and size.

"That would be something," Everitt said, his eyes widening.

posted by prof_booty | 03:31 PM