Relativistic Firehose Instability
In this work, we study the firehose instability in expanding relativistic plasmas using kinetic simulations, with the goal of understanding how pressure anisotropy is generated, how transverse magnetic fluctuations grow, and how the classical firehose threshold is modified in relativistic regimes. Transverse magnetic-field fluctuations generated by the relativistic firehose instability during the expansion-driven growth of pressure anisotropy.
