Instantaneous spreading and Einstein causality in quantum theory
نویسنده
چکیده
In nonrelativistic quantum mechanics the wave-function of a free particle which initially is in a ÿnite volume immediately spreads to inÿnity. In a nonrelativistic theory this is of no concern, but we show that the same instantaneous spreading can occur in relativistic quantum theory and that transition probabilities in widely separated systems may instantaneously become nonzero. We discuss how this aþects Einstein causality.
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