The Kosterlitz-Thouless transition
The Kosterlitz-Thouless transition
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科斯特利茨-托利斯转变
DOI:
10.1007/3-540-11192-1_5
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发表时间:
1982
期刊:
影响因子:
--
通讯作者:
T. Spencer
中科院分区:
文献类型:
--
作者:
J. Fröhlich;T. Spencer
The purpose of this talk is to describe a new method for proving the existence of phase transitions. In particular we shall discuss the Kosterlitz-Thouless transition for the two dimensional plane rotator and the existence of a spontaneous magnetization for the one dimensional Ising model with i/r 2 interaction. There are basically three ways to establish the existence of phase transitions:(a) Exact solution. This technique applies to a very limited class of models such as the two dimensional Ising model and the ice model, but gives a detailed description of the nature of the transition. See [i].(b) The Peierls argument (1936) applies to a wide variety of models which have at most a discrete symmetry group. These models include the 3 dimensional Ising model and the anisotropic Heisenberg model.(c) The infrared bounds [2] are applicable to three or more dimensional spin systems with continuous internal symmetry, such as the isotropic nearest neighbor Heisenberg model. The method gives reasonably good lower bounds on the critical temperature but is restricted to reflection positive spin systems. In both (b) and (c) an order parameter, typically long range order, is needed to characterize the transi£ ion. The method we shall discuss in this lecture combines a duality transformation with block spin methods. The duality transformation is basically a Fourier series expansion and replaces the 0 (2) symmetry of the rotator, by a discrete symmetry~. Our basic estimates are essentially a more refined version of the energy entropy inequalities which appear in the proof of the Peierls argument. This method is applicable to a wide variety of models including the solid on solid model, the four dimensional U (1) gauge model [see also Guth [3] for earlier results], and the 2 dimensional~ clock models, n