Abstract
We explore higher-dimensional conformal field theories (CFTs) in the presence of a conformal defect that itself hosts another sub-dimensional defect. We refer to this new kind of conformal defect as the composite defect. We elaborate on the various conformal properties of the composite defect CFTs, including correlation functions, operator expansions, and conformal block expansions. As an example, we present a free O(N) vector model in the presence of a composite defect. Assuming the averaged null energy condition (ANEC) does hold even for the defect systems, we conclude that some boundary conditions can be excluded. Our investigations shed light on the rich phenomenology arising from hierarchical defect structures, paving the way for a deeper understanding of critical phenomena in nature.
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Acknowledgments
The author is particularly grateful to Tatsuma Nishioka for stimulating discussions on various points in this paper and encouraging the author to write this paper. The author is also grateful to Dongsheng Ge for discussions relating this project. The work of S. S. was supported by Grant-in-Aid for JSPS Fellows No. 23KJ1533.
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Shimamori, S. Conformal field theory with composite defect. J. High Energ. Phys. 2024, 131 (2024). https://doi.org/10.1007/JHEP08(2024)131
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DOI: https://doi.org/10.1007/JHEP08(2024)131