Page:Grundgleichungen (Minkowski).djvu/25

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.

Now by putting , the differential equation (29) is transformed into the same form as eq. (1) here when . Therefore it so happens that by a compensation of two contradictions to the relativity principle, the differential equations of Lorentz for moving non-magnetised bodies at last agree with the relativity postulate.

If we make use of (30) for non-magnetic bodies, and put accordingly , then in consequence of (C) in §8,


i.e. for the direction of


and for a perpendicular direction ,


i.e. it coincides with Lorentz's assumption, if we neglect in comparison to 1.

Also to the same order of approximation, Lorentz's form for corresponds to the conditions imposed by the relativity principle [comp. (E) § 8] — that the components of , are equal to the components of multiplied by or respectively.

§ 10. Fundamental Equations of E. Cohn.

E. Cohn[1] assumes the following fundamental equations

(32) ,

where E, M are the electric and magnetic field intensities (forces), are the electric and magnetic polarisation (induction).

  1. Gött. Nachr. 1901, w. 74 (also in Ann. d. Phys. 7 (4), 1902, p. 29).