Abstract
We prove that Haag duality holds for cones in the toric code model. That is, for a cone Λ, the algebra \({\mathcal{R}_{\Lambda}}\) of observables localized in Λ and the algebra \({\mathcal{R}_{\Lambda^c}}\) of observables localized in the complement Λc generate each other’s commutant as von Neumann algebras. Moreover, we show that the distal split property holds: if \({\Lambda_1 \subset \Lambda_2}\) are two cones whose boundaries are well separated, there is a Type I factor \({\mathcal{N}}\) such that \({\mathcal{R}_{\Lambda_1} \subset \mathcal{N} \subset \mathcal{R}_{\Lambda_2}}\) . We demonstrate this by explicitly constructing \({\mathcal{N}}\) .
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Acknowledgments
This research is funded by the Netherlands Organisation for Scientific Research (NWO) grant no. 613.000.608. The author wishes to thank Klaas Landsman, Michael Müger and Reinhard Werner for valuable feedback on the manuscript.
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Naaijkens, P. Haag Duality and the Distal Split Property for Cones in the Toric Code. Lett Math Phys 101, 341–354 (2012). https://doi.org/10.1007/s11005-012-0572-7
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DOI: https://doi.org/10.1007/s11005-012-0572-7
Mathematics Subject Classification (2010)
- 81R15 (46L60, 81T05, 82B20)
Keywords
- Haag duality
- distal split property
- toric code