Plasmatillståndet

Plasmatillståndet, often referred to as the fourth state of matter, is a state where a gas has been energized to the point that some or all of its atoms or molecules have lost or gained electrons, becoming ionized. This results in a collection of charged particles, specifically ions and free electrons, along with neutral atoms or molecules. Unlike a normal gas, plasma is electrically conductive and can interact strongly with electromagnetic fields.

The transition to plasma typically occurs at very high temperatures, although it can also be achieved at lower temperatures through strong electric fields or radiation. The energy input causes electrons to be stripped from their atoms, creating a plasma composed of ions and electrons. These charged particles are in constant motion and interact with each other through electromagnetic forces.

Plasmas are ubiquitous in the universe. Stars, including our Sun, are primarily composed of plasma. Terrestrial examples include lightning, the aurora borealis, and the flames of a fire. In technology, plasma is utilized in various applications such as fluorescent lighting, plasma screens, plasma torches for cutting and welding, and in fusion energy research. The behavior of plasma is governed by complex electromagnetic and kinetic theories.