Deviation from the exponential decay law in relativistic quantum field theory: the example of strongly decaying particles

TL;DR

This paper demonstrates that deviations from exponential decay occur in relativistic quantum field theory, suggesting the possibility of quantum Zeno effects in elementary particle decays, with strong deviations observed in meson decay rates like the rho meson.

Contribution

It shows the existence of short-time deviations from exponential decay in relativistic quantum field theory, extending the quantum Zeno effect to elementary particle decays.

Findings

Deviations from exponential decay occur in relativistic quantum field theory.

Strong deviations are present during the mean lifetime of mesons.

The rho meson exemplifies significant decay law deviations.

Abstract

We show that a short-time regime, in which a deviation from the exponential decay law occurs, exists also in the framework of a superrenormalizable relativistic quantum field theory. This, in turn, implies the possibility of a quantum Zeno effect also for elementary decays. The attention is then focused on the typical order of magnitude of strong decay rates of mesons: for these particles, strong deviations from the exponential decay law are present during a period of time comparable with their mean life time. As a concrete example, the case of the $\rho $ meson is studied.