Z2-indices and Hedetniemi's conjecture

Takahiro Matsushita

The ${\mathbb{Z}}_2$-index $\mathrm{ind}(X)$ of a ${\mathbb{Z}}_2$-CW-complex $X$ is the smallest number $n$ such that there is a ${\mathbb{Z}}_2$-map from $X$ to $S^n$. Here we consider $S…