Albert Einstein was a young clerk in a Swiss patent office when he began the work that led to the General Theory of Relativity. SF State physics Professor James Lockhart was a doctoral student at Stanford University l3 years ago when he began the pioneering research in sensitive instrument measurements to test Einstein's 80-year-old theory.
The work of both men is set to converge in the first ever fundamental physics experiment to be performed in space, targeted for launch by NASA in December l999.
"The whole framework of physics could rest on the outcome of this experiment," said Joseph Taylor, winner of the l993 Nobel Prize in physics.
But first, the project known as Gravity Probe B, must fight the seventh and probably final battle of its political life as its funder, NASA, faces the worst budget crisis in its 37-year history. NASA must reduce its budget by $5 billion over the next five years, said its chief scientist, France Cordova. "It's hard to put a price tag on science," Cordova said. She claimed that "every mission has either been completely restructured or canceled by us or by Congress." And GP-B, also known as The Relativity Mission, though termed a "delicate project" by Cordova, is no exception.
The project, almost as old as the space agency itself, was developed in l962 at Stanford University.
Calling GP-B NASA's third most costly space and science mission, Cordova said NASA will have spent $220 million on the project by Oct. l. Cordova said an additional $342 million remains to be spent on the project between then and 1999.
The costs, coupled with what Cordova described as "anxiety in the scientific community concerning this project," have led NASA to appoint a l3-member "blue ribbon" review panel to evaluate the project, made up of two Nobel laureates and other eminent scientists and headed by Val Fitch of Princeton University.
Cordova said NASA will support the outcome of the panel fully, "unless more cuts come down -- then all bets are off."
"No one I know of believes the project is unworthy -- the real problem is the priority in funding," said Taylor, who is a member of the evaluating panel for the project. The official report will be submitted to NASA headquarters on June l.
Paradoxically for Lockhart, Cordova said NASA asked the panel to evaluate two essential questions that focus on the measurement method Lockhart developed for the project.
Calling Lockhart's role a crucial one, GP-B Principal Investigator Francis Everitt of Stanford University said "Jim is one of half a dozen people who are key to the project."
According to Einstein, a large body like the earth warps space much like a marble would dent a bedsheet it was lying on. This is known as the geodetic effect.
If you rotated the marble on the bedsheet, the sheet would twist slightly. Einstein predicted a similar effect in space as the earth, while rotating, pulls space around with it. This effect is called frame-dragging and GP-B is the only experiment ever devised to test its existence.
According to Everitt, Lockhart developed the method to which GP-B will measure the frame-dragging effect to a precision of one percent or better and the geodetic effect to one part in l0,000. "Think of the width of a human hair as seen from a distance of l0 miles -- this is the angle Lockhart is trying to measure," said Everitt.
Working on GP-B full time for two years at Stanford University and part time for ll years at SF State, Lockhart leads a team of five graduate students who are paid on an hourly basis for their work on the project. Saying the project "enhanced my teaching, makes me stay up to date with new concepts and approaches and stay in touch with others in similar fields." Lockhart pointed out that the project also "works out well for the graduate students," because their affiliation with it enables them to go on to competitive postgraduate programs.
To test the theory, the GP-B spacecraft will be equipped with four gyroscopes -- instruments that study the earth's rotation by means of freely suspended flywheels -- trained on a guide star.
If Einstein's theory is correct, the frame-dragging and geodetic effects will gradually change the spin direction of the gyroscopes, causing a slight drift from the guide star due to the warping of time and space.
Cordova said NASA asked the panel to evaluate whether the level of accuracy this experiment could achieve was important as a scientific measurement and, more importantly, if the technical approach ensured this level of accuracy with high probability.
Lockhart said the 1 percent uncertainty factor is considered a good first measurement by scientific standards.
"The intensity in this project has been in the preparation and in taking enough care to think everything through -- every potential error, every source of disturbance must be accounted for," Lockhart said.
But the project is not without its detractors. GP-B has sparked a level of debate in the physics community involving some of the most eminent scientists in the nation.
"Frame-dragging itself has not been measured, but on the basis of other experiments performed, we expect it to occur," said Jeremiah Ostriker, chairman of the department of astrophysical sciences at Princeton. So much so in fact, Ostriker said "as Plumian Professor of Astronomy at Cambridge, Sir Martin Rees said, if this experiment tells us anything other than what we already know, we won't believe it!"
Ostriker, who said he voiced his doubts about the project with NASA Administrator Daniel Goldin, called GP-B "a good experiment that should be done if costs were no object."
Cordova said it would be inappropriate, in light of the GP-B review, to comment on her own feelings about GP-B.
But, said Cordova "I know how I feel in my heart about GP-B. I'm a physicist. I'm a scientist."
Announcing Einstein's death 4l years ago in this month, the New York Times called him "one of the greatest thinkers of the ages."
Einstein himself may have spoken the best epitaph to this story. "Politics are for the moment. An equation is for eternity," he said.
Editors note: The General Theory of Relativity is the correct name, not the Theory of Relativity. (DV)