The relativistic Doppler effect: when a zero-frequency shift or a red shift exists for sources approaching the observer
Article first published online: 20 DEC 2010
Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Annalen der Physik
Volume 523, Issue 3, pages 239–246, March 2011
How to Cite
Wang, C. (2011), The relativistic Doppler effect: when a zero-frequency shift or a red shift exists for sources approaching the observer. Ann. Phys., 523: 239–246. doi: 10.1002/andp.201000099
- Issue published online: 7 FEB 2011
- Article first published online: 20 DEC 2010
- Manuscript Accepted: 2 DEC 2010
- Manuscript Revised: 27 NOV 2010
- Manuscript Received: 4 AUG 2010
- Doppler effect;
- relativistic red shift for approaching;
- free-electron lasers.
It is shown without making use of Lorentz transformation that there exists a phenomenon of relativistic zero-frequency shift in Doppler effect for a plane wave in free space, observed in two inertial frames of relative motion, and the zero shift takes place at a maximum aberration of light. When it is applied to analysis of a moving point light source, two unconventional physical implications result: (1) a light source, when it is approaching (moving closer to) the observer, may cause a red shift; (2) a zero-frequency-shift observation does not necessarily mean that the light source is not moving closer, and in contrast, the light source may be moving closer to the observer at a high speed. This fundamental result of special relativity may provide an alternative way to experimentally examine the principle of relativity, and might have a significant application in astrophysics.