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May 20, 2020 at 11:51 comment added YCor PS in this paper (M. Choban, L. Chiriac, Selected problems and results of topological algebra, Romai J., v.9, no.1(2013), 1–25, ), it is stated that among spheres, only those of dimension $0,1,3,7$ admit a topological quasigroup structure (that is, a topological E-structure).
May 20, 2020 at 7:13 comment added YCor In general a on a (compact) closed topological manifold $X$ an E-structure is the same as a continuous map $i:X\to\mathrm{Homeo}(X)$ such that for any distinct $x,y\in X$, $i(x)^{-1}i(y)$ has no fixed point. Just the property of admitting uncountably many self-homeomorphism pairwise with no common fixed point is restrictive: among spheres it selects odd-dimensional ones. Among surfaces it only selects the 2-torus and the Klein bottle. So far I'm unable to figure out whether the Klein bottle or the 5-sphere admit such structures, anyway.
May 20, 2020 at 6:37 history answered YCor CC BY-SA 4.0