Abstract
Graph comparison is a certain type of condition on the metric space encoded by a finite graph. We show that each nontrivial graph comparison implies one of Alexandrov’s comparisons. The proof gives a complete description of graphs with trivial graph comparisons.
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Acknowledgments
We thank Alexander Lytchak for help.
Funding
The first author was partially supported by the Russian Foundation for Basic Research (Grant no. 20–01–00070); the second author was partially supported by the National Science Foundation (Grant no. DMS–2005279) and the Ministry of Science and Higher Education of the Russian Federation (Grant no. 075–15–2022–289).
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Translated from Sibirskii Matematicheskii Zhurnal, 2023, Vol. 64, No. 3, pp. 579–584. https://doi.org/10.33048/smzh.2023.64.310
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Lebedeva, N.D., Petrunin, A.M. Graph Comparison Meets Alexandrov. Sib Math J 64, 624–628 (2023). https://doi.org/10.1134/S0037446623030102
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DOI: https://doi.org/10.1134/S0037446623030102