PARALLEL UNIVERSES 235
powerful particle accelerators, they found scores of new particles spitting out. It was so frustrating that J. Robert Oppenheimer declared that
the Nobel Prize in Physics should go to the physicist who did not discover a new particle that year! (Enrico Fermi, horrified at the proliferation of subatomic particles with Greek-sounding names, said, "If I
could remember the names of all these particles, I would have become
a botanist") After decades of hard work, this zoo of particles could be
arranged into something called the Standard Model. Billions of dollars,
the sweat of thousands of engineers and physicists, and twenty Nobel
Prizes have gone into painfully assembling, piece by piece, the Standard Model. It is a truly remarkable theory, which seems to fit all the
experimental data concerning subatomic physics.
But the Standard Model, for all its experimental successes, suffered
from one serious defect. As Stephen Hawking says, "It is ugly and ad
hoc." It contains at least nineteen free parameters (including the particle masses and the strength of their interactions with other particles),
thirty-six quarks and antiquarks, three exact and redundant copies of
sub-particles, and a host of strange-sounding subatomic particles,
such as tau neutrinos, Yang-Mills gluons, Higgs bosons, W bosons, and
Z particles. Worse, the Standard Model makes no mention of gravity. It
seemed hard to believe that nature, at its most supreme, fundamental
level, could be so haphazard and supremely inelegant. Here was a theory only a mother could love. The sheer inelegance of the Standard
Model forced physicists to reanalyze all their assumptions about nature. Something was terribly wrong.
If one analyzes the last few centuries in physics, one of the most
important achievements of the last century was to summarize all fundamental physics into two great theories: the quantum theory (represented by the Standard Model) and Einstein's theory of general
relativity (describing gravity). Remarkably, together they represent the
sum total of all physical knowledge at a fundamental level. The first
theory describes the world of the very small, the subatomic quantum
world where particles perform a fantastic dance, darting in and out of
existence and appearing two places at the same time. The second theory describes the world of the very large, such as black holes and the
powerful particle accelerators, they found scores of new particles spitting out. It was so frustrating that J. Robert Oppenheimer declared that
the Nobel Prize in Physics should go to the physicist who did not discover a new particle that year! (Enrico Fermi, horrified at the proliferation of subatomic particles with Greek-sounding names, said, "If I
could remember the names of all these particles, I would have become
a botanist") After decades of hard work, this zoo of particles could be
arranged into something called the Standard Model. Billions of dollars,
the sweat of thousands of engineers and physicists, and twenty Nobel
Prizes have gone into painfully assembling, piece by piece, the Standard Model. It is a truly remarkable theory, which seems to fit all the
experimental data concerning subatomic physics.
But the Standard Model, for all its experimental successes, suffered
from one serious defect. As Stephen Hawking says, "It is ugly and ad
hoc." It contains at least nineteen free parameters (including the particle masses and the strength of their interactions with other particles),
thirty-six quarks and antiquarks, three exact and redundant copies of
sub-particles, and a host of strange-sounding subatomic particles,
such as tau neutrinos, Yang-Mills gluons, Higgs bosons, W bosons, and
Z particles. Worse, the Standard Model makes no mention of gravity. It
seemed hard to believe that nature, at its most supreme, fundamental
level, could be so haphazard and supremely inelegant. Here was a theory only a mother could love. The sheer inelegance of the Standard
Model forced physicists to reanalyze all their assumptions about nature. Something was terribly wrong.
If one analyzes the last few centuries in physics, one of the most
important achievements of the last century was to summarize all fundamental physics into two great theories: the quantum theory (represented by the Standard Model) and Einstein's theory of general
relativity (describing gravity). Remarkably, together they represent the
sum total of all physical knowledge at a fundamental level. The first
theory describes the world of the very small, the subatomic quantum
world where particles perform a fantastic dance, darting in and out of
existence and appearing two places at the same time. The second theory describes the world of the very large, such as black holes and the