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Computational Complexity of Topological Invariants

Published online by Cambridge University Press:  11 December 2014

Manuel Amann*
Department of Mathematics, University of Toronto, Earth Sciences 2146, Toronto, ON M5S 2E4, Canada


We answer the following question posed by Lechuga: given a simply connected space X with both H* (X; ℚ) and π*(X) ⊗ ℚ being finite dimensional, what is the computational complexity of an algorithm computing the cup length and the rational Lusternik—Schnirelmann category of X?

Basically, by a reduction from the decision problem of whether a given graph is k-colourable for k ≥ 3, we show that even stricter versions of the problems above are NP-hard.

Research Article
Copyright © Edinburgh Mathematical Society 2015 

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