EPILOGUE 297
People left string theory in droves to work on QCD. All the funding,
jobs, and recognition went to physicists working on the quark model.
I remember those dark years well. Only the foolhardy or the stubborn persisted in working on string theory. And when it became known
that these strings could vibrate only in ten dimensions, the theory became the butt of jokes. String pioneer John Schwarz at Cal Tech would
sometimes bump into Richard Feynman in the elevator. Ever the joker,
Feynman would ask, "Well, John, and how many dimensions are you in
today?" We used to joke that the only place to find a string theorist was
in the unemployment line. (Nobel laureate Murray Gell-Mann, founder
of the quark model, once confided to me that he took pity on string theorists and created a "nature preserve for endangered string theorists" at
Cal Tech so people like John wouldn't lose their jobs.)
Given that today so many young physicists are rushing to work on
string theory, Steve Weinberg has written, "String theory provides our
only present source of candidates for a final theory-how could anyone
expect that many of the brightest young theorists would not work
on it?"
Is STRING THEORY UNTESTABLE?
One major criticism of string theory today is that it is untestable. It
would take an atom smasher the size of the galaxy to test this theory,
critics claim.
But this criticism neglects the fact that most science is done indirectly, not directly. No one has ever visited the sun to do a direct test,
but we know it is made of hydrogen because we can analyze its spectral lines.
Or take black holes. The theory of black holes dates back to 1783,
when John Michell published an article in the Philosophical Transactions of the Royal Society He claimed that a star could be so massive
that "all light emitted from such a body would be made to return to it
by its own proper gravity." MichelPs "dark star" theory languished for
People left string theory in droves to work on QCD. All the funding,
jobs, and recognition went to physicists working on the quark model.
I remember those dark years well. Only the foolhardy or the stubborn persisted in working on string theory. And when it became known
that these strings could vibrate only in ten dimensions, the theory became the butt of jokes. String pioneer John Schwarz at Cal Tech would
sometimes bump into Richard Feynman in the elevator. Ever the joker,
Feynman would ask, "Well, John, and how many dimensions are you in
today?" We used to joke that the only place to find a string theorist was
in the unemployment line. (Nobel laureate Murray Gell-Mann, founder
of the quark model, once confided to me that he took pity on string theorists and created a "nature preserve for endangered string theorists" at
Cal Tech so people like John wouldn't lose their jobs.)
Given that today so many young physicists are rushing to work on
string theory, Steve Weinberg has written, "String theory provides our
only present source of candidates for a final theory-how could anyone
expect that many of the brightest young theorists would not work
on it?"
Is STRING THEORY UNTESTABLE?
One major criticism of string theory today is that it is untestable. It
would take an atom smasher the size of the galaxy to test this theory,
critics claim.
But this criticism neglects the fact that most science is done indirectly, not directly. No one has ever visited the sun to do a direct test,
but we know it is made of hydrogen because we can analyze its spectral lines.
Or take black holes. The theory of black holes dates back to 1783,
when John Michell published an article in the Philosophical Transactions of the Royal Society He claimed that a star could be so massive
that "all light emitted from such a body would be made to return to it
by its own proper gravity." MichelPs "dark star" theory languished for