|MadSci Network: Chemistry|
According to most textbooks, there are four phases of matter. Three of these are familiar from everyday life: solid, liquid, and gas. The fourth phase is plasma, which is gas that's so hot it's ionized. Plasma is a soup of electrons and positively ionized atoms found in the upper atmosphere and in the Sun.
In 1995, physicists created a new phase of matter known as Bose-Einstein Condensate, which was predicted in 1924 by Einstein and Bose, and Indian scientist [more information available in the MadSci Archives]. This condensate is extremely cool, only a tiny fraction of a degree above absolute zero.
At the other extreme, particle physicists have used giant particle accelerators to create a state of matter that previously existed only shortly after the Big Bang and perhaps inside neutron stars. This stuff, called quark-gluon plasma is similar to a regular plasma except that it is so hot that protons and neutrons break up into quarks so the quarks are free to move around like the electrons in an ordinary plasma.
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