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arXiv · 1610.09685

Free compact boson on branched coverings of the torus

Feihu Liu
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Abstract

We have studied the free compact boson on a $n$-sheeted covering of the torus gluing alone $m$ branch cuts. It is interesting because when the branched cuts are chosen to be real, the partition function is related to the $n$-th R\'enyi entanglement entropy of $m$ disjoint intervals in a finite system at finite temperature. After proposing a canonical homology basis and its dual basis of the covering surface, we find that the partition function can be written in terms of theta functions.

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Feihu Liu. 2016-10-30. Free compact boson on branched coverings of the torus. https://doi.org/10.1016/j.physletb.2017.05.058

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