plasma summary

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Below is the article summary. For the full article, see plasma.

plasma, Electrically conducting medium in which there are roughly equal numbers of positively and negatively charged particles, produced when the atoms in a gas become ionized (see ionization). Plasma is sometimes called the fourth state of matter (the first three being solid, liquid, and gas). A plasma is unique in the way it interacts with itself, with electric and magnetic fields, and with its environment. It can be thought of as a collection of ions, electrons, neutral atoms and molecules, and photons in which some atoms are being ionized at the same time as electrons are recombining with other ions to form neutral particles, while photons are continuously being produced and absorbed. It is estimated that more than 99% of the matter in the universe exists in the plasma state.

Lev Davidovich Landau Summary

Lev Davidovich Landau was a Soviet theoretical physicist, one of the founders of the quantum theory of condensed matter whose pioneering research in this field was recognized with the 1962 Nobel Prize for Physics. Landau was a mathematical prodigy and enfant terrible. His schooling reflected the