Absence of Ordering in Certain Classical Systems
- 1 May 1967
- journal article
- Published by AIP Publishing in Journal of Mathematical Physics
- Vol. 8 (5) , 1061-1064
- https://doi.org/10.1063/1.1705316
Abstract
A classical inequality giving lower bounds for fluctuations about ordered states is derived. The inequality, analogous to a quantum result due to Bogoliubov, is established by a purely classical argument which makes explicit the nature of the surface boundary conditions required, a point which is rather obscure in the quantum derivations. As in the quantum case the inequality is useful in excluding certain kinds of phase transitions in one‐ and two‐dimensional systems. This is illustrated for several kinds of classical spin systems.Keywords
This publication has 3 references indexed in Scilit:
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- Long-wavelength excitations and the Goldstone theorem in many-particle systems with ?broken symmetries?The European Physical Journal A, 1966
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