Relativistic approach to thermodynamic irreversibility

We consider a localized quantum system living in a curved spacetimes. By translating into this scenario the paradgmatic two-point measument scheme in quantum statistical mechanics we are able to prove a relativistic version of the quantum flutuation theorem. One of the consequences of such a theorem is that entropy production is deeply observer dependent. The main ideas of this chapter are published in [M. L. W. Basso, J. Maziero and L. C. C\'eleri. The irreversibility of relativistic time-dilation. Class. Quantum Grav. \textbf{40}, 195001 (2023); M. L. W. Basso, J. Maziero and L. C. C\'eleri. Quantum detailed fluctuation theorem in curved spacetimes: the observer dependent nature of entropy production. Phys. Rev. Lett. \textbf{134}, 050406 (2025)].