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arXiv · 1504.00138

Infinite circumference limit of conformal field theory

Nobuyuki Ishibashi·Tsukasa Tada
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Abstract

We argue that an infinite circumference limit can be obtained in 2-dimensional conformal field theory by adopting $L_0-(L_1+L_{-1})/2$ as a Hamiltonian instead of $L_0$. The theory obtained has a circumference of infinite length and hence exhibits a continuous and heavily degenerated spectrum as well as the continuous Virasoro algebra. The choice of this Hamiltonian was inspired partly by the so-called sine-square deformation, which is found in the study of a certain class of quantum statistical systems. The enigmatic behavior of sine-square deformed systems such as the sharing of their vacuum states with the closed boundary systems can be understood by the appearance of an infinite circumference.

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Nobuyuki Ishibashi, Tsukasa Tada. 2015-07-17. Infinite circumference limit of conformal field theory. https://doi.org/10.1088/1751-8113%2F48%2F31%2F315402

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