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Why can plasma behave collectively even when its particles rarely collide?

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How scientists use lasers to learn about the universe — plasma Learn about the PHELIX (Petawatt High-Energy Laser for Heavy Ion Experiments) laser at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. PHELIX is used for plasma and atomic physics research.

Plasma can behave collectively even when particle collisions are infrequent because its constituents interact through long-range electromagnetic forces rather than relying solely on short-range physical collisions.1

In a plasma, charged particles—such as electrons and ions—exert forces on one another over significant distances. When a group of particles is displaced from equilibrium, these long-range electrostatic attractions create restoring forces that cause the particles to oscillate in an organized, collective manner. Because these interactions are strong and pervasive, the particles move together as a whole, exhibiting behaviors like plasma oscillations and wave propagation.23

Essentially, the collective nature of plasma arises because the motion of any single charged particle influences, and is influenced by, the electric field and magnetic field generated by the entire ensemble of particles. This allows the plasma to maintain a coherent, jellylike behavior even in the absence of frequent individual particle collisions.41