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arXiv · 2403.19830

Emerging Jordan blocks in the two-dimensional Potts and loop models at generic $Q$

Lawrence Liu·Jesper Lykke Jacobsen·Hubert Saleur
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Abstract

It was recently suggested -- based on general self-consistency arguments as well as results from the bootstrap (arXiv:2005.07708, arXiv:2007.11539, arXiv:2007.04190) -- that the CFT describing the $Q$-state Potts model is logarithmic for generic values of $Q$, with rank-two Jordan blocks for $L_0$ and ${\mkern 1.5mu\overline{\mkern-1.5mu L\mkern-1.5mu}\mkern 1.5mu}_0$ in many sectors of the theory. This is despite the well-known fact that the lattice transfer matrix (or Hamiltonian) is diagonalizable in (arbitrary) finite size. While the emergence of Jordan blocks only in the limit $L\to\infty$ is perfectly possible conceptually, diagonalizability in finite size makes the measurement of logarithmic couplings (whose values are analytically predicted in arXiv:2007.11539, arXiv:2007.04190) very challenging. This problem is solved in the present paper (which can be considered a companion to arXiv:2007.11539), and the conjectured logarithmic structure of the CFT confirmed in detail by the study of the lattice model and associated "emerging Jordan blocks."

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Lawrence Liu, Jesper Lykke Jacobsen, Hubert Saleur. 2024-03-28. Emerging Jordan blocks in the two-dimensional Potts and loop models at generic $Q$. https://arxiv.org/abs/2403.19830

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