On the Physical Meaning of Maxwell Stress Tensor

맥스웰 응력텐서의 물리적 의미의 고찰

  • 최홍순 (경북대학교 전자전기공학부) ;
  • 박일한 (성균관대학교 정보통신공학부) ;
  • 문원규 (포항공과대학교 기계공학과)
  • Published : 2009.04.01

Abstract

Maxwell stress tensor is one of the methods which are generally used for electromagnetic force calculation. In this paper, it is presented that Maxwell stress tensor T and n${\cdot}$T have no physical meaning and therefore should not be used as sources of mechanical force for deformations or dynamics. The divergence of Maxwell stress tensor ${\nabla}{\cdot}T$ is the one which can acquire a physical identity and is electromagnetic body force density by an action at a distance like a gravity. This result can be derived from the principle of power balance, and also verified by some thought experiments. The virtual air-gap approach is proposed as a valid solution for the calculation of the body force.

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