Showing 2026Show all
2 papers · 1 filter
math.SG2026
A non-orderable overtwisted contact structure on the sphere
Jakob Hedicke
We show that the overtwisted contact structure on with Hopf invariant is non-orderable, i.e., that it admits a contractible positive loop of contactopmorphisms. This pro…
math.SG2026
Bott-integrable contact forms with large systolic ratio
Hansjörg Geiges, Jakob Hedicke, Murat Sağlam
We show that there is no universal upper bound for the systolic ratio of Bott-integrable contact forms on closed 3-manifolds, thus providing further evidence for the relative flexi…