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arXiv · 2302.06178

A topological version of Hedetniemi's conjecture for equivariant spaces

Vuong Bui·Hamid Reza Daneshpajouh
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Abstract

A topological version of the famous Hedetniemi conjecture says: The mapping index of the Cartesian product of two $\mathbb Z/2$-spaces is equal to the minimum of their $\mathbb Z/2$-indexes. The main purpose of this article is to study the topological version of the Hedetniemi conjecture for $G$-spaces. Indeed, we show that the topological Hedetniemi conjecture cannot be valid for general pairs of $G$-spaces. More precisely, we show that this conjecture can possibly survive if the group $G$ is either a cyclic $p$-group or a generalized quaternion group whose size is a power of 2.

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Vuong Bui, Hamid Reza Daneshpajouh. 2023-02-13. A topological version of Hedetniemi's conjecture for equivariant spaces. https://doi.org/10.1007/s00493-023-00079-8

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