The no-boundary condition and the other theories are just proposals
for the boundary conditions of the universe. To test them we have to
calculate what predictions they make and compare them with the
new observations that are coming in. At the moment, the
observations are not good enough to distinguish between these
different kinds of maps. But new observations in the next few years
may settle the question. This is an exciting time in cosmology. My money is on the no-
boundary condition. It is such an elegant explanation, I’m sure God would have chosen it.
The progress that has been made in unifying gravity with the other forces has been entirely
theoretical. This has led to charges from people like John Horgan that physics is dead because
it has become just a mathematical game, not related to experiment. But I don’t agree.
Although we can’t produce particles of the Planck energy — the energy at which gravity
would be unified with other forces — there are predictions that can be tested at lower energies.
The Superconducting Super Collider that was being built in Texas would have reached these
energies but it was cancelled when the U.S. went through a fit of feeling poor. So we shall
have to wait for the Large Hadron Collider that is being built in Geneva.
Assuming that the Geneva experiments confirm current theory, what are the prospects for a
complete unified theory? In 1980 I said I thought there was a 50-50 chance of us finding a
complete unified theory in the next 20 years. That is still my estimate, but the 20 years begins
now. I will be back in another 20 years to tell you if we made it.
Professor Stephen Hawking of the University of Cambridge spoke to a sellout crowd at Convocation
Hall April 27, 1998. The event was sponsored by the Global Knowledge Foundation.