Preserving quantum information in $f(Q)$ cosmology

Abstract: The effects of cosmological expansion on quantum bosonic states are investigated, using quantum information theory. In particular, a generic Bogoliubov transformation of bosonic field modes is considered and the state change on a single mode is regarded as the effect of a quantum channel. Properties and capacities of this channel are thus explored in the framework of $f(Q)$ theories. As immediate result, we obtain that the information on a single-mode state appears better preserved, whenever the number of particles produced by the cosmological expansion is small. Hence, similarly to general relativity, we show that analogous particle productions result even if we consider symmetric teleparallel gravity theories. Thus, we investigate a power law $f(Q)$ model, leaving unaltered the effective gravitational coupling, and minimise the corresponding particle production. We thus show how to optimise the preservation of classical and quantum information, stored in a bosonic mode states in the remote past. Finally, we compare our findings with those obtained in general relativity.