4 citations · 9 across the 10 of their papers we have counts for
6 papers · 1 filter
A splitting criterion for two-dimensional semi-tori
Joerg Winkelmann
We investigate conditions under which a two-dimensional complex semi-torus splits into a direct product of C^* and a one-dimensional compact complex torus.
On Varieties with trivial logarithmic tangent bundle
Joerg Winkelmann
We characterize Kaehler manifolds with trivial logarithmic tangent bundle (with respect to a divisor D) as a class of certain compatifications of complex semi-tori.
Bounds for Curves in Abelian Varieties
Junjiro Noguchi, Joerg Winkelmann
A uniform bound of intersection multiplicities of curves and divisors on abelian varieties is proved by algebraic geometric methods. It extends and improves a result obtained by A.…
On Elliptic Curves in SL_2(C)/Γ, Schanuel's conjecture and geodesic lengths
Joerg Winkelmann
Let H be a discrete cocompact subgroup of SL_2(C). We conjecture that the quotient manifold X=SL_2(C)/H contains infinitely many non-isogeneous elliptic curves and prove that this…
Invariant Rings and Quasiaffine Quotients
Joerg Winkelmann
We study Hilbert's fourteenth problem from a geometric point of view. Nagata's celebrated counterexample demonstrates that for an arbitrary group action on a variety the ring of in…
Subvarieties of C^n with non-extendible Automorphisms
Harm Derksen, Frank Kutzschebauch, Joerg Winkelmann
We investigate algebraic and analytic subvarieties of C^n with automorphisms which can not be extended to the ambient space.