Localization and causality for a free particle
Abstract
Theorems (most notably by Hegerfeldt) prove that an initially localized particle whose time evolution is determined by a positive Hamiltonian will violate causality. We argue that this apparent paradox is resolved for a positive energy free particle described by either the Dirac equation or the Klein-Gordon equation because such a particle cannot be localized in the sense required by the theorems.
- Publication:
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Physics Letters A
- Pub Date:
- February 2003
- DOI:
- arXiv:
- arXiv:quant-ph/0111060
- Bibcode:
- 2003PhLA..308..110B
- Keywords:
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- Quantum Physics
- E-Print:
- 9 pages,no figures,new section added