A quantum critical point is a special class of continuous phase transition that takes place at the absolute zero of temperature, typically in a material where the phase transition temperature has been driven to zero by the application of a pressure, field or through doping. Conventional phase transitions occur at finite temperature, when the growth of random thermal fluctuations leads to a change in the physical state of a system. Condensed matter physics research over the past few decades has revealed a new class of phase transitions, called a quantum phase transition, which take place at absolute zero, and which are driven by the zero point quantum fluctuations associated with Heisenberg's uncertainty principle.
Read more about Quantum Critical Point: Overview, Quantum Critical Endpoints, Non-equilibrium Quantum Phase Transition
Famous quotes containing the words quantum, critical and/or point:
“A personality is an indefinite quantum of traits which is subject to constant flux, change, and growth from the birth of the individual in the world to his death. A character, on the other hand, is a fixed and definite quantum of traits which, though it may be interpreted with slight differences from age to age and actor to actor, is nevertheless in its essentials forever fixed.”
—Hubert C. Heffner (1901–1985)
“It is a sign of our times, conspicuous to the coarsest observer, that many intelligent and religious persons withdraw themselves from the common labors and competitions of the market and the caucus, and betake themselves to a certain solitary and critical way of living, from which no solid fruit has yet appeared to justify their separation.”
—Ralph Waldo Emerson (1803–1882)
“The parents who wish to lead a quiet life I would say: Tell your children that they are very naughty—much naughtier than most children; point to the young people of some acquaintances as models of perfection, and impress your own children with a deep sense of their own inferiority. You carry so many more guns than they do that they cannot fight you. This is called moral influence and it will enable you to bounce them as much as you please.”
—Samuel Butler (1835–1902)