Do Atoms Age?

TL;DR

This paper explores whether quantum systems like radioactive ions exhibit aging effects over time, proposing an experimental test in ion clocks that could reveal deviations from standard quantum mechanics.

Contribution

It introduces a novel experimental approach to detect aging in single-particle quantum systems and demonstrates that such effects can occur in certain non-linear quantum theories.

Findings

Aging effects are absent in standard quantum mechanics.

Causal non-linear modifications predict observable aging effects.

Proposed ion clock experiment can test for quantum aging phenomena.

Abstract

Time evolution generically entangles a quantum state with environmental degrees of freedom. The resulting increase in entropy changes the properties of that quantum system leading to "aging". It is interesting to ask if this familiar property also applies to simple, single particle quantum systems such as the decay of a radioactive particle. We propose a test of such aging in an ion clock setup where we probe for temporal changes to the energies of the electronic state of an ion containing a radioactive nucleus. Such effects are absent in standard quantum mechanics and this test is thus a potent null test for violations of quantum mechanics. As a proof of principle, we show that these effects exist in causal non-linear modifications of quantum mechanics.