Spin-projection orientations in the plane square-lattice Ising model with periodic boundary conditions

You-gang Feng

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Spin-projection orientations in the plane square-lattice Ising model with periodic boundary conditions

You-gang Feng

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Abstract

The periodic boundary conditions changed the plane square-lattice Ising model to the torus-lattice system which restricts the spin-projection orientations. Only two of the three important spin-projection orientations, parallel to the x-axis or to the y-axis, are suited to the torus-lattice system. The infinitesimal difference of the free-energies of the systems between the two systems mentioned above makes their critical temperatures infinitely close to each other, but their topological fundamental groups are distinct.

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You-gang Feng. 2005-06-29. Spin-projection orientations in the plane square-lattice Ising model with periodic boundary conditions. https://arxiv.org/abs/quant-ph/0506202

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