Space plasmas in various astrophysical setups can often be both very hot and
dilute, making them highly susceptible to waves and fluctuations, which are
generally self-generated and maintained by kinetic instabilities. In this
sense, we have in-situ observational evidence from the solar wind and planetary
environments, which reveal not only wave fluctuations at kinetic scales of
electrons and protons, but also non-equilibrium distributions of particle
velocities. This paper reports on the progress made in achieving a consistent
modeling of the instabilities generated by temperature anisotropy, taking
concrete example of those induced by anisotropic electrons, such as,
electromagnetic electron-cyclotron (whistler) and firehose instabilities. The
effects of the two main electron populations, the quasi-thermal core and the
suprathermal halo indicated by the observations, are thus captured. The
low-energy core is bi-Maxwellian, and the halo is described for the first time
by a regularized (bi-)$\kappa$-distribution (RKD), which was recently
introduced to fix inconsistencies of standard $\kappa$-distributions (SKD). In
the absence of a analytical RKD dispersion kinetic formalism (involving tedious
and laborious derivations), both the dispersion and (in)stability properties
are directly solved numerically using the numerical Arbitrary Linear Plasma
Solver (ALPS). The results have an increased degree of confidence, considering
the successful testing of the ALPS on previous results with established
distributions.

Este artículo explora los viajes en el tiempo y sus implicaciones.

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