  When multiple species interact with an electrostatic ion acoustic wave, they
can exchange momentum, despite the lack of momentum in the field itself. The
resulting force on the electrons can have a curl, and thus give rise to
compensating electric fields with curl on magnetohydrodynamic timescales. As a
result, a magnetic field can be generated. Surprisingly, in some astrophysical
settings, this mechanism can seed magnetic fields with growth rates even larger
than through the traditional Biermann battery.
