Chapel Hill Conference
The Conference on the Role of Gravitation in Physics, better known as the Chapel Hill Conference or GR1, was an invitation-only international scientific conference held at Chapel Hill, North Carolina, United States, from January 18 to January 23, 1957. Attendees discussed topics in gravitational physics, including general relativity, gravitational waves, radio astronomy, cosmology, and quantum gravity. It was also the first conference where the many-worlds interpretation was discussed.
The Chapel Hill Conference one of the first in an ongoing series of modern conferences on gravitation, referred to as GRn. It followed the one convened in Bern, Switzerland, on the 50th anniversary of special relativity, GR0, taking place just a few months after the death of Albert Einstein. After the Chapel Hill Conference, conferences on general relativity and gravitation much larger gatherings, fueled by advances in observational astronomy; the discovery of pulsars, quasars, X-ray sources, the cosmic microwave background, and the first black-hole candidate ; among other developments. By the 1980s, conferences of this kind had hundreds of attendees from dozens of countries worldwide.
According to historian of physics Dean Rickles, the Chapel Hill Conference revived interest in general relativity, similar to what the 1947 Shelter Island Conference did for quantum field theory. Physicist Dennis Sciama explained its significance thusly, "This was the real beginning on one sense, that is, it brought together isolated people, showed that they had reached a common set of problems, and inspired them to continue working. The 'relativity family' was born then."
Organization
The conference was organized by the Institute of Field Physics established a year before the conference in the University of North Carolina at Chapel Hill. The institute was financed by industrialist Agnew Hunter Bahnson.The conference was organized by physicists Cécile DeWitt-Morette and Bryce DeWitt. Aside from the DeWitts, in the steering committee there was also Frederik Belinfante, Peter Bergmann, Freeman Dyson and John Archibald Wheeler.
The conference was divided into 4 sessions on unquantized general relativity, a single session on cosmology, and 3 sessions on quantum gravity.
Discussed topics
Lack of new experiments
After the introductory lecture by Wheeler, Robert H. Dicke reviewed the experimental tests of general relativity. He concluded that there was not much progress, he contrasted it with quantum mechanics:Dicke discussed the Eötvös experiment and provided ideas for further experiments.
Gravitational waves
During the conference, the nature of gravitational waves and their ability to transfer energy was discussed. Richard Feynman remembersFelix Pirani presented for the first time how to mathematically treat gravitational waves using the geodesic deviation introduced by John Lighton Synge. He showed how two masses would move relative from each other from ripples in spacetime. Based on Pirani's argument, Feynman suggested during the conference the sticky bead argument which intuitively demonstrated that gravitational waves must carry energy. A version of this argument was published by Hermann Bondi right after the conference.
Wormholes
During the conference, Wheeler coined the term wormhole.Numerical relativity
When discussing the presentations of Yvonne Fourès-Bruhat and Charles W. Misner, Bryce DeWitt pointed out the importance of using computers to solve Einstein field equations. This line of research led to the development of numerical relativity.Many-worlds interpretation
The relative state formulation, better known today as the many-worlds interpretation of quantum mechanics, was being developed by Hugh Everett III, a student of Wheeler, who submitted an edited version of his thesis for the conference but did not attend. The paper was well received by Bryce DeWitt. Wheeler and Charles W. Misner presented some of Everett's ideas near the end of the conference. Feynman publicly criticized the idea of an universal wavefunction, suggested by Wheeler, sayingEverett's paper was published in the proceedings of the conference.