Publications

Publications of SPP2026

On this site you find preprints and publications produced within the projects and with the support of the DFG priority programme „Geometry at Infinity“.

51The geometry of locally symmetric manifolds via natural maps

We show that for every \(n \geq 2\) and \(D > 0\) there exist a convex domain \(\Omega \subseteq \mathbb{H}^n\) with diameter \(D\) and a convex potential \(V\) on \(\Omega\) such that the fundamental gap of the operator \(-\Delta + V\) is strictly smaller than the fundamental gap of  \(-\Delta\). In comparison to previous work, this result requires more refined control of the eigenfunctions.

 

Related project(s):
51The geometry of locally symmetric manifolds via natural maps

We show that if a closed manifold of dimension at least four admits a negatively curved metric that is almost Einstein in a suitable sense, then it admits a genuine Einstein metric of negative sectional curvature. Importantly, the pinching constant measuring the almost-Einstein condition neither depends on an upper bound for the diameter or volume, nor on a lower bound for the injectivity radius.

 

Related project(s):
51The geometry of locally symmetric manifolds via natural maps

For every \(n \geq 4\) we construct infinitely many mutually not homotopic closed manifolds of dimension \(n\) which admit a negatively curved Einstein metric but no locally symmetric metric.

 

JournalTo apper in Journal of the European Mathematical Society (JEMS).
Link to preprint version

Related project(s):
51The geometry of locally symmetric manifolds via natural maps

Extending earlier work of Tian, we show that if a manifold admits a metric that is almost hyperbolic in a suitable sense, then there exists an Einstein metric that is close to the given metric in the \(C^{2,\alpha}\)-topology. In dimension 3 the original manifold only needs to have finite volume, and the volume can be arbitrarily large. Applications include a new proof of the hyperbolization of 3-manifolds of large Hempel distance yielding some new geometric control on the hyperbolic metric, and an analytic proof of Dehn filling and drilling that allows the filling and drilling of arbitrary many cusps and tubes.

 

Related project(s):
51The geometry of locally symmetric manifolds via natural maps