TITLE:
Can the Abraham Light Momentum and Energy in a Medium Constitute a Lorentz Four-Vector?
AUTHORS:
Changbiao Wang
KEYWORDS:
Light Momentum in a Medium; Principle of Relativity; Optical Pulling Effect
JOURNAL NAME:
Journal of Modern Physics,
Vol.4 No.8,
August
14,
2013
ABSTRACT: By analyzing the Einstein-box thought experiment with the principle
of relativity, it is shown that Abraham’s light momentum and energy in a medium
cannot constitute a Lorentz four-vector, and they consequentially break global
momentum and energy conservation laws. In
contrast, Minkowski’s momentum and energy always constitute a Lorentz
four-vector no matter whether in a medium or in vacuum, and the Minkowski’s
momentum is the unique correct light momentum. A momentum-associated
photon mass in a medium is exposed, which explains why only the Abraham’s
momentum is derived in the traditional “center-of-mass-energy” approach. The EM
boundary-condition matching approach, combined with Einstein light-quantum
hypothesis, is proposed to analyze this thought experiment, and it is found for
the first time that only from Maxwell equations without resort to the
relativity, the correctness of light momentum definitions cannot be identified.
Optical pulling effect is studied as well.