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:
“He had killed and put to earth so many that his sword broke in two. At length he thought to himself that that was enough massacring and killing for one day, and that the rest should be allowed to escape in order to spread the news.”
—François Rabelais (14941553)
“Both of us felt more anxiety about the Southabout the colored people especiallythan about anything else sinister in the result. My hope of a sound currency will somehow be realized; civil service reform will be delayed; but the great injury is in the South. There the Amendments will be nullified, disorder will continue, prosperity to both whites and colored people will be pushed off for years.”
—Rutherford Birchard Hayes (18221893)