Hadron properties in the nuclear medium

The QCD vacuum shows the dynamical breaking of chiral symmetry. In the hot and/or dense QCD medium, the chiral order parameter such as ⟨q̄q⟩ is expected to change as a function of temperature T and density ρ of the medium, and its experimental detection is one of the main challenges in modern hadron physics. In this paper, the theoretical expectations for the in-medium hadron spectra associated with partial restoration of chiral symmetry are discussed as well as the current status of experiments with an emphasis on the measurements of properties of mesons produced in near-ground-state nuclei.