Abstract
Using the ordered analogue of Farley–Sabalka’s discrete gradient field on the configuration space of a graph, we unravel a levelwise behavior of the generators of the pure braid group on a tree. This allows us to generalize Farber’s equivariant description of the homotopy type of the configuration space on a tree on two particles. The results are applied to the calculation of all the higher topological complexities of ordered configuration spaces on trees on any number of particles.
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Notes
All cohomology groups in this paper are taken with \({\mathbb {Z}}\)-coefficients.
It suffices to totally order the non-deleted edges adjacent to v.
Stacks like these are uniquely determined, as the tree has been assumed to be n-sufficiently subdivided.
In this kind of expressions we extend, in the obvious way, the abuse of terminology in (10).
An \(a_0\)-local T-branch is a sequence of edges \((a_0,b), (b,c), (c,d),\ldots \) (it implies \(a_0<b<c<d<\ldots \)).
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Aguilar-Guzmán, J., González, J. & Hoekstra-Mendoza, T. Farley–Sabalka’s Morse-Theory Model and the Higher Topological Complexity of Ordered Configuration Spaces on Trees. Discrete Comput Geom 67, 258–286 (2022). https://doi.org/10.1007/s00454-021-00306-3
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DOI: https://doi.org/10.1007/s00454-021-00306-3
Keywords
- Discretized configuration space on a tree
- Discrete Morse theory
- Farley–Sabalka gradient field
- Topological complexity