It seems pretty cut and dry, insofar as these things can be. There are established processes that cause the spontaneous creation of particle pairs in sufficiently energetic electric fields, and an analogous process for photons, both being part of the same QFT field. It's sort of sad, I always liked the idea of a kugelblitz, and this seems to render it totally impossible by any realistic astrophysical or even artificial process.
It seems pretty cut and dry, insofar as these things can be. There are established processes that cause the spontaneous creation of particle pairs in sufficiently energetic electric fields, and an analogous process for photons, both being part of the same QFT field. It's sort of sad, I always liked the idea of a kugelblitz, and this seems to render it totally impossible by any realistic astrophysical or even artificial process.