collaborators

6 papers

math.CV2026

Stein spaces and Stein algebras

Olivier Benoist

We prove that the category of Stein spaces and holomorphic maps is anti-equivalent to the category of Stein algebras and -algebra morphisms. This removes a finite dimen…

math.AG2026

The Brauer group of a Stein algebra

Olivier Benoist, James Hotchkiss

We investigate the Brauer group of the ring of holomorphic functions on a finite-dimensional Stein space S. We provide a purely topological computation of this gro…

math.AG2026

The resultant divisor is negative

Olivier Benoist

Fix two integers . We study the birational geometry of a parameter space for pairs of homogeneous polynomials of degrees and in two variables (in which the highe…

math.AG2025

On the field of meromorphic functions on a Stein surface

Olivier Benoist

We prove that fields of meromorphic functions on Stein surfaces have cohomological dimension 2, and solve the period-index problem and Serre's conjecture II for these fields. We ob…

math.AG2025

The Pythagoras number of fields of transcendence degree over

Olivier Benoist

We show that any sum of squares in a field of transcendence degree over is a sum of squares, answering a question of Pop and Pfister. We deduce this result fro…

math.CV2025

On the Artin vanishing theorem for Stein spaces

Olivier Benoist

Artin vanishing theorems for Stein spaces refer to the vanishing of some of their (co)homology groups in degrees higher than the dimension. We obtain new positive and negative resu…