On QED plasmas*

Quantum electrodynamics (QED) effects are interesting phenomena that occur in strong electromagnetic fields. Advances in laser technology brought lab experiments close to the regime where they become important. Furthermore, astrophysical systems such as strongly magnetized neutrons stars and magnetars possess magnetic fields close to or even stronger than the Schwinger (critical) field. Whereas some QED effects are being incorporated in plasma codes, theoretical studies of QED plasmas are lacking. Here we derive the general equation describing QED plasma modes. We discuss the properties of the low-frequency modes, for which the transitions between the Landau levels can be neglected.