Borge Nodland
Borge Nodland | |
|---|---|
| Nationality | American |
| Known for | Claimed indication of cosmological anisotropy ("cosmic birefringence") |
| Scientific career | |
| Fields | Physics, cosmology |
Borge Nodland is an American physicist known for a 1997 claim of evidence for anisotropy in the propagation of electromagnetic radiation across the universe. He is listed in The Worldwide List of Dissident Scientists in the "Cosmology" category.
Cosmic birefringence claim
In 1997, Nodland and John P. Ralston published "Indication of Anisotropy in Electromagnetic Propagation over Cosmological Distances" in Physical Review Letters (vol. 78, p. 3043). Analyzing the polarization of radio galaxies, they reported a systematic rotation of the plane of polarization correlated with distance and direction, independent of ordinary Faraday rotation, which they interpreted as a possible new cosmological effect with a "birefringence" length scale of order 10^25 meters. They connected the proposed effect to the geometric (Pancharatnam-Berry) phase, describing a corkscrew-like twisting of the polarization plane.
The claim attracted considerable media attention as a possible sign of a preferred direction, or "axis," in the universe, challenging the assumption of cosmic isotropy. It was quickly and widely criticized: several groups argued the reported correlation was a statistical artifact and not supported by independent analyses of the polarization data. The result is not accepted by the cosmology mainstream, though searches for cosmic birefringence have continued as an active area of research.