Hot, ionized gases, also known as plasmas, do not experience enough collisions for them to have a scalar, equilibrium temperature.
The non-equilibrium structures in the distribution of particle velocities in such systems change the collective behavior of waves.
We consider examples of these changes using measurements from the plasma instrument on Parker Solar Probe, which measures the solar atmosphere as close as seven million kilometers from the Sun's surface, where non-equilibrium velocity structures are frequently observed.
Sometimes these changes allow waves to propagate further before damping or how energy from the damping is distributed between charged particle populations.
In other examples, the non-equilibrium structure enhances the emission of waves.
These changes can not be found in analytic models for wave behavior.
This supports more sophisticated treatment of heating in future models of hot plasma systems in our solar system and throughout the universe.