We show that virtual particles, despite being unobservable, can be described by quantum operators which can be interpreted under certain conditions as valid quantum states with interesting connections to quantum information. For virtual fermions, we prove that such states can be regarded as 2-qubit thermal states and study their entanglement. For spin-1 virtual bosons and virtual pairs of fermions, we find them to be associated to 4-qubit operators containing all the details of the interactions. Finally, we study how renormalization affects these results. These findings represent new connections between quantum field theory, quantum information and quantum thermodynamics.
With support from FCT through project UIDB/00777/2020