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arXiv · 1707.05812

Universal entropy of conformal critical theories on a Klein bottle

Hong-Hao Tu
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Abstract

We show that rational conformal field theories in 1+1 dimensions on a Klein bottle, with length $L$ and width $β$, satisfying $L \gg β$, have a universal entropy. This universal entropy is a topological invariant depending on the quantum dimensions of the primary fields and can be accurately extracted by taking a proper ratio between the Klein bottle and torus partition functions, enabling a characterization of conformal critical theories. The result is checked against exact calculations in quantum spin-1/2 XY and Ising chains.

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Hong-Hao Tu. 2018-01-08. Universal entropy of conformal critical theories on a Klein bottle. https://doi.org/10.1103/physrevlett.119.261603

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