geometry-topology / Complex algebraic geometry; universal covers and fundamental groups
The Shafarevich conjecture on holomorphic convexity of universal covers
Surface manuscript, Theorem 1.1: a smooth connected projective complex surface X containing a connected nodal curve Z0 with smooth rational components such that π1(Z0)→π1(X) has infinite image; a component of its preimage in X is a closed noncompact union of compact rational curves, so hulls are noncompact and X is not holomorphically convex. By the linear Shafarevich theorem π1(X) has no faithful finite-dimensional complex representation. Fourfold manuscript, Theorem 1.1: a smooth projective fourfold with large fundamental group (no positive-dimensional compact subvariety in X) whose universal cover is not Stein, hence not holomorphically convex; this disproves the large-fundamental-group form as well. Neither paper addresses quasi-projective or Kahler variants beyond these.
Surface manuscript, Theorem 1.1: a smooth connected projective complex surface X containing a connected nodal curve Z0 with smooth rational components such that π1(Z0)→π1(X) has infinite image; a component of its preimage in X is a closed noncompact union of compact rational curves, so hulls are noncompact and X is not holomorphically convex. By the linear Shafarevich theore…
Surface manuscript, Theorem 1.1: a smooth connected projective complex surface X containing a connected nodal curve Z0 with smooth rational components such that π1(Z0)→π1(X) has infinite image; a component of its preimage in X is a closed noncompact union of compact rational curves, so hulls are noncompact and X is not holomorphically convex. By the linear Shafarevich theorem π1(X) has no faithful finite-dimensional complex representation. Fourfold manuscript, Theorem 1.1: a smooth projective fourfold with large fundamental group (no positive-dimensional compact subvariety in X) whose universal cover is not Stein, hence not holomorphically convex; this disproves the large-fundamental-group form as well. Neither paper addresses quasi-projective or Kahler variants beyond these.
Surface manuscript, Theorem 1.1: a smooth connected projective complex surface X containing a connected nodal curve Z0 with smooth rational components such that π1(Z0)→π1(X) has infinite image; a component of its preimage in X is a closed noncompact union of compact rational curves, so hulls are noncompact and X is not holomorphically convex. By the linear Shafarevich theorem π1(X) has no faithful finite-dimensional complex representation. Fourfold manuscript, Theorem 1.1: a smooth projective fourfold with large fundamental group (no positive-dimensional compact subvariety in X) whose universal cover is not Stein, hence not holomorphically convex; this disproves the large-fundamental-group form as well. Neither paper addresses quasi-projective or Kahler variants beyond these.