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In physics, a state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. Many intermediate states are known to exist, such as liquid crystal, and some states only exist under extreme conditions, such as Bose–Einstein condensates, neutron-degenerate matter, and quark–gluon plasma, which only occur, respectively, in situations of extreme cold, extreme density, and extremely high energy. For a complete list of all exotic states of matter, see the list of states of matter.
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The lambda point is the temperature at which normal fluid helium makes the transition to superfluid helium II. The lowest pressure at which He-I and He-II can coexist is the vapor−He-I−He-II triple point at 2.1768 K (−270.9732 °C) and 5.048 kPa (0.04982 atm), which is the "saturated vapor pressure" at that temperature. The highest pressure at which He-I and He-II can coexist is the bcc−He-I−He-II triple point with a helium solid at 1.762 K (−271.388 °C), 29.725 atm (3,011.9 kPa).
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William P. Halperin is a Canadian-American physicist, academic, and researcher. He is the Orrington Lunt Professor of Physics at Northwestern University.
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References
- ↑ Frustration in Modulated Phases: Ripples and Boojums, from Europhysics Letters , 5 (4), pp. 327-331 (1988); by J. M. Carlson, S.A. Langer, and J. P. Sethna; archived at Cornell University
- ↑ Kwan, Alex (2005-09-15). "Boojums help turn physicist and pianist David Mermin into offbeat science writer". Cornell Chronicle. Retrieved 2017-10-11.
- N. David Mermin (15 March 1990). Boojums All the Way Through: Communicating Science in a Prosaic Age . Cambridge University Press. p. xii. ISBN 978-0-521-38880-1. A collection of articles by David Mermin, including "E pluribus boojum".