The conversion of high-energy photons into electron–positron pairs is a known phenomenon. The required photon energy scale is determined by the rest energy of the pair, which is about 1 MeV.

A model for dense degenerate plasmas that incorporates electron spin indicates that quantum effects can be seen even under conditions previously considered to be in the classical regime.

Specifically, the plasmas at these extreme conditions are known as relativistic electron-positron pair plasmas because they comprise a collection of electrons and positrons—all flying around at ...