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arXiv · hep-th/9706173

Phase structure of four-dimensional gonihedric spin system

G. Koutsoumbas·G. K. Savvidy·K. G. Savvidy
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Abstract

We perform Monte Carlo simulations of a gauge invariant spin system which describes random surfaces with gonihedric action in four dimensions. The Hamiltonian is a mixture of one-plaquette and additional two- and three-plaquette interaction terms with specially adjusted coupling constants. For the system with the large self-intersection coupling constant $k$ we observe the second-order phase transition at temperature $β_{c}\simeq 1.75$. The string tension is generated by quantum fluctuations as it was expected theoretically. This result suggests the existence of a noncritical string in four dimensions. For smaller values of $k$ the system undergoes the first order phase transition and for $k$ close to zero exhibits a smooth crossover.

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G. Koutsoumbas, G. K. Savvidy, K. G. Savvidy. 1997-06-25. Phase structure of four-dimensional gonihedric spin system. https://doi.org/10.1016/s0370-2693(97)00978-7

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