? meson condensation ? resonances Beth-Uhlenbeck equation of state GW170817 Gamma-ray bursts Gravitational waves Mott dissociation QCD matter QCD phase diagram Quantum Chromodynamics axion QED chiral symmetry cluster virial expansion cold-dense QCD collective flow combustion critical point crystalline structure deconfinement dense matter directed flow equation of state finite density finite size finite temperature general relativity gravitational waves hadronic matter hadron–quark continuity heavy-ion collisions