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On the stability of one particle states generated by quantum fields fulfilling Yang-Feldman equations

H. Gottschalk
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Abstract

We prove that for a Wightman quantum field $\phi(x)$ the assumptions (i) positivity of the metric on the state space ${\cal H}$ of the theory (ii) the asymptotic condition in the form of Yang-Feldman equations and (iii) Klein-Gordon equation for the outgoing field imply that the states generated by application of the asymptotic fields to the vacuum are stable. We prove by a counter example that this statement is wrong in the case of quantum fields with indefinite metric.

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H. Gottschalk. 2004-08-25. On the stability of one particle states generated by quantum fields fulfilling Yang-Feldman equations. https://doi.org/10.1016/s0034-4877(01)80039-2

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