2025/11/10 by Yakov Bloch, Avshalom C. Elitzur, Bloch, Yakov +1
Physics and Astronomy · #Quantum and Classical Electrodynamics #Atomic and Molecular Physics #Quantum Electrodynamics and Casimir Effect
paper · pdf · doi:10.48550/arxiv.2511.07195
Relativistic time dilation implies that an accelerating excited atom would have its lifetime prolonged in the lab frame. In this paper, we demonstrate a complementary effect: Longer-lived excited atoms turn out to have been accelerated. We propose the following experiment. An excited atom is prepared in a superposition of momenta. Due to relativistic time dilation, in the lab frame, the decay rate of components with higher momentum is diminished. As time passes without the atom emitting a photon, higher-momentum components become more probable. This results in a time-dependent shift of the expectation value of momentum. Taking into account first-order relativistic corrections, we calculate the force and acceleration undergone by the atom due to the fact that it did not emit a photon.