M ar 1 99 9 DIAS - STP - 98 - 13 Localizing the Relativistic Electron
نویسنده
چکیده
A causally well-behaved solution of the localization problem for the free electron is given, with natural space-time transformation properties , in terms of Dirac's position operator x. It is shown that, although x is not an observable in the usual sense, and has no positive-energy (generalized) eigenstates, the 4-vector density (ρ(x, t), j(x, t)/c) is observable , and can be localized arbitrarily precisely about any point in space, at any instant of time, using only positive-energy states. A suitable spin operator can be diagonalized at the same time.
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تاریخ انتشار 2008