Abstract
We prove that the ordered configuration spaces of planar graphs have the highest possible topological complexity generically, as predicted by a conjecture of Farber. Our argument establishes the same generic maximality for all higher topological complexities. We include some discussion of the non-planar case, demonstrating that the standard approach to the conjecture fails at a fundamental level.
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Acknowledgements
The author thanks Byung Hee An and Jesus Gonzalez for helpful conversations. Special thanks are due to Andrea Bianchi, who discovered the error in an incorrect proof of the general case of Farber’s conjecture appearing in an earlier version. The author learned of Farber’s conjecture at the AIM workshop “Configuration spaces of graphs” and was reminded of it at the BIRS–CMO workshop “Topological complexity and motion planning.” While writing, the author benefited from the hospitality of the MPIM and was supported by NSF grant DMS 1906174.
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Knudsen, B. Farber’s conjecture for planar graphs. Sel. Math. New Ser. 27, 90 (2021). https://doi.org/10.1007/s00029-021-00702-w
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DOI: https://doi.org/10.1007/s00029-021-00702-w