Rationally connected varieties over local fields.
Real singular Del Pezzo surfaces and 3-folds fibred by rational curves, II
Let be a real smooth projective 3-fold fibred by rational curves such that is orientable. J. Kollár proved that a connected component of is essentially either Seifert fibred or a connected sum of lens spaces. Answering three questions of Kollár, we give sharp estimates on the number and the multiplicities of the Seifert fibres (resp. the number and the torsions of the lens spaces) when is a geometrically rational surface. When is Seifert fibred over a base orbifold , our result generalizes...
Reduction of the proof of the non-rationality of a non-singular cubic threefold to a result of mumford
Relations between moduli spaces of stable bundles over ...2 and rationality.
Schichten von Matrizen sind rationale Varietäten.
Smooth Rational Curves on Enriques Surfaces.
Smoothing Cusp Singularities of Small Length.
Smoothings of cusp singularities via triangle singularities
Some more examples of curves in P3 with stable normal bundle.
Some Results on Unirationality of Algebraic Surfaces.
Stable rationality of certain PGLn-quotients.
Stably rational algebraic tori
The rationality of a stably rational torus with a cyclic splitting field is proved.
Surfaces rationnelles non-spéciales dans IP4.
The Bogomolov multiplier of groups of order and exponent
We conduct an in-depth investigation into the structure of the Bogomolov multiplier for groups of order and exponent . We present a comprehensive...
The Hasse problem for rational surfaces.
The Hodge Conjecture for Fourfolds Admitting a Covering by Rational Curves.
The jacobian map, the jacobian group and the group of automorphisms of the Grassmann algebra
There are nontrivial dualities and parallels between polynomial algebras and the Grassmann algebras (e.g., the Grassmann algebras are dual of polynomial algebras as quadratic algebras). This paper is an attempt to look at the Grassmann algebras at the angle of the Jacobian conjecture for polynomial algebras (which is the question/conjecture about the Jacobian set– the set of all algebra endomorphisms of a polynomial algebra with the Jacobian – the Jacobian conjecture claims that the Jacobian...
The Modell-Weil groups of unirational quasi-elliptic surfaces in characteristic 3.
The non rationality of the generic Enriques' threefold
The rationality of some moduli spaces of plane curves