Problems / geometry-topology
geometry-topology / Complex geometry; differential topology
The (3,4,∞) Modular Family of 2-Tori as a Complex Structure on S6
Claims an explicit compact complex threefold X, fibred over P1 by complex 2-tori via period functions on the (3,4,∞) orbifold, degenerating to a del Pezzo-of-degree-six fibre (identified opposite sides of its hexagon) at one point and to bielliptic multiple fibres of multiplicities 3 and 4 at the other two. Argues X is simply connected with H∗(X;Z)=H∗(S6;Z), hence diffeomorphic to S6, with algebraic dimension exactly 1. This directly contradicts [CDP20, Cor. 2.3], a published (and once-corrected) theorem; the paper states this and argues where the two accounts diverge, rather than overlooking it. Posted hours before this entry, with no independent check, no formalisation, and no refutation yet in any venue found. Filed as a candidate specifically because none of that has happened, not because a problem with the argument has been found.