Order And Disorder (physics)
In physics, the terms order and disorder designate the presence or absence of some symmetry or correlation in a many-particle system.
In condensed matter physics, systems typically are ordered at low temperatures; upon heating, they undergo one or several phase transitions into less ordered states. Examples for such an order-disorder transition are:
- the melting of ice: solid-liquid transition, loss of crystalline order;
- the demagnetization of iron by heating above the Curie temperature: ferromagnetic-paramagnetic transition, loss of magnetic order.
The degree of freedom that is ordered or disordered can be translational (crystalline ordering), rotational (ferroelectric ordering), or a spin state (magnetic ordering).
The order can consist either in a full crystalline space group symmetry, or in a correlation. Depending on how the correlations decay with distance, one speaks of long-range order or short-range order.
If a disordered state is not in thermodynamic equilibrium, one speaks of quenched disorder. For instance, a glass is obtained by quenching (supercooling) a liquid. By extension, other quenched states are called spin glass, orientational glass. In some contexts, the opposite of quenched disorder is annealed disorder.
Read more about Order And Disorder (physics): Quenched Disorder, Annealed Disorder
Famous quotes containing the words order and/or disorder:
“All grandeur, all power, all subordination to authority rests on the executioner: he is the horror and the bond of human association. Remove this incomprehensible agent from the world and at that very moment order gives way to chaos, thrones topple and society disappears.”
—Joseph De Maistre (17531821)
“A. Well, an old order is a violent one.
This proves nothing. Just one more truth, one more
Element in the immense disorder of truths.”
—Wallace Stevens (18791955)