Editing Bose–Einstein condensate (section)

==== Velocity-distribution data graph ====
In the image accompanying this article, the velocity-distribution data indicates the formation of a Bose–Einstein condensate out of a gas of [[rubidium]] atoms. The false colors indicate the number of atoms at each velocity, with red being the fewest and white being the most. The areas appearing white and light blue are at the lowest velocities. The peak is not infinitely narrow because of the [[uncertainty principle|Heisenberg uncertainty principle]]: spatially confined atoms have a minimum width velocity distribution. This width is given by the curvature of the magnetic potential in the given direction. More tightly confined directions have bigger widths in the ballistic velocity distribution. This [[anisotropy]] of the peak on the right is a purely quantum-mechanical effect and does not exist in the thermal distribution on the left. This graph served as the cover design for the 1999 textbook ''Thermal Physics'' by Ralph Baierlein.<ref>{{cite book |url=https://archive.org/details/thermalphysics00ralp|url-access=registration|title=Thermal Physics|author=Baierlein, Ralph |publisher=Cambridge University Press|year=1999|isbn=978-0-521-65838-6}}</ref>