J.J. Thomson and “Hidden” Momentum
نویسندگان
چکیده
The term “hidden momentum” was introduced by Shockley [1] in 1967 to describe the small amount of net mechanical momentum that must exist in systems “at rest” that have nonzero electromagnetic field momentum. The classic example is a current loop (Ampèrian magnetic dipole) in an external static electric field (perhaps due to a single electric charge) [4, 5]. This example had been considered by J.J. Thomson in 1904 [7, 8, 9], when he deduced via two different methods that the field momentum is (in Gaussian units)
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