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Plasma

Plasma is, one which we do not observe naturally on earth or on our sister planets because it requires a great deal of energy. When lightning comes down it may turn the atmospheric molecules into a plasma -- but only for am instant. Scientists have been able to produce plasma under very special conditions in their labs. In plasma, the atoms have absorbed even more energy than in they gaseous state and are now ionized. This means that many of the atoms have lost electrons, which are now loose in the plasma. The matter in stars is in the plasma state.

A Bose?Einstein condensate is a state of matter formed by bosons cooled to temperatures very near to absolute zero (0 kelvin or -273.15°C). Under such supercooled conditions, a large fraction of the atoms collapse into the lowest quantum state, at which point quantum effects become apparent on a macroscopic scale.

This state of matter was first predicted as a consequence of quantum mechanics by Albert Einstein

Theory

The slowing of atoms by use of cooling apparatuses produces a singular quantum state known as a Bose condensate or Bose?Einstein condensate. This phenomenon was predicted in 1925 by Albert Einstein, by generalizing Satyendra Nath Bose's work on the statistical mechanics of (massless) photons to (massive) atoms (The Einstein manuscript, believed to be lost, was found in a library at Leiden University in 2005. The result of the efforts of Bose and Einstein is the concept of a Bose gas, governed by the Bose?Einstein statistics, which describes the statistical distribution of identical particles with integer spin, now known as bosons. Bosonic particles, which include the photon as well as atoms such as helium-4, are allowed to share quantum states with each other. Einstein speculated that cooling bosonic atoms to a very low temperature would cause them to fall (or "condense") into the lowest accessible quantum state, resulting in a new form of matter.

This transition occurs below a critical temperature, which for a uniform three-dimensional gas consisting of non-interacting particles with no apparent internal degrees of freedom is given by:

$T_c=left( rac{n}{zeta(3/2)} ight)^{2/3} rac{h^2}{2cdotpicdot mcdot k_B}$

where:

$,T_c$	is	the critical temperature,
$,n$		the particle density,
$,m$		the mass per boson,
$,h$		Planck's constant,
$,k_B$		the Boltzmann constant, and
$,zeta$		the Riemann zeta function; $,zeta(3/2)$ ? 2.6124.

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