107 citations · 194 across the 26 of their papers we have counts for
32 papers
Local-global principles for the existence of Levi factors
David Harbater, Julia Hartmann, George McNinch
We discuss local-global principles for the existence of Levi factors (i.e., complements to the unipotent radical) for linear algebraic groups over one-variable function fields. We…
Finiteness of formal pushforwards
David Harbater, Julia Hartmann, Daniel Krashen
Under mild hypotheses, given a scheme and an open subset whose complement has codimension at least two, the pushforward of a torsion-free coherent sheaf on is coherent…
Bounding cohomology classes over semiglobal fields
David Harbater, Julia Hartmann, Daniel Krashen
We provide a uniform bound for the index of cohomology classes in when is a semiglobal field (i.e., a one-variable function field over a complete…
Adelic double cosets over semi-global fields
David Harbater
Double coset spaces of adelic points on linear algebraic groups arise in the study of global fields; e.g., concerning local-global principles and torsors. A different type of doubl…
Local-global principles for constant reductive groups over semi-global fields
Jean-Louis Colliot-Thélène, David Harbater, Julia Hartmann +3
We study local-global principles for torsors under reductive linear algebraic groups over semi-global fields; i.e., over one variable function fields over complete discretely value…
The differential Galois group of the rational function field
Annette Bachmayr, David Harbater, Julia Hartmann +1
We determine the absolute differential Galois group of the field of rational functions: It is the free proalgebraic group on a set of cardinality . Th…