Splitting the mapping class group extension for connected sums of equal-dimensional sphere products
Determine whether the exact sequence relating the Torelli group, the mapping class group, and the group G_g splits for the connected sum of g copies of S^p × S^p when g = 1 and p = 7.
References
For $g = 1$, when $p = 3$ it does not split by , and the case $p = 7$ is open.
— Mapping class groups of simply connected closed spin 5-manifolds with no 2- and 3-torsion in homology
(2608.26698 - Jin, 27 Aug 2026) in Remark in Section 1.1, item (3)