Issue
EPL
Volume 79, Number 1, July 2007
Article Number 10006
Number of page(s) 4
Section General
DOI http://dx.doi.org/10.1209/0295-5075/79/10006
Published online 18 June 2007
EPL, 79 (2007) 10006
DOI: 10.1209/0295-5075/79/10006

The invariance of the phase of waves among inertial frames is questionable

Young-Sea Huang

Department of Physics, Soochow University - Shih-Lin, Taipei, Taiwan

yshuang@mail.scu.edu.tw

received 3 May 2007; accepted in final form 29 May 2007; published July 2007
published online 18 June 2007

Abstract
Two types of relativistic transformation for the four-vector $(\omega /c,{\bf k})$ of waves (including light waves in media, or acoustic waves) are obtained based on the differential Lorentz transformation. One of them is just the usual Lorentz transformation, whereas the second one is not. The second one is required to secure the frequency of waves from being negative, in the case that the speed of waves in a medium is less than the speed of that medium moving in the direction opposite to the propagation direction of waves. Therefore, the four-vector $(\omega /c,{\bf k})$ of waves is in general not Lorentz-covariant. The invariance of the phase of waves among inertial frames is questionable.

PACS
03.30.+p - Special relativity.

© Europhysics Letters Association 2007