The Twin Paradox in Quantum Field Theory

Vacuum fluctuations in quantum field theory impose fundamental limitations on our ability to measure time in short scales. To investigate the impact of universal quantum field theory effects on observer-dependent time measurements, we introduce a clock model based on the vacuum decay probability of a finite-sized quantum system. Using this model, we study a microscopic twin paradox scenario and find that, in the smallest scales, time is not only dependent on the trajectory connecting two events, but also on how vacuum fluctuations interact with the microscopic details of the clocks.