Average signature of geodesic paths in compact Lie groups

Abstract

For any compact connected Lie group $G$, we introduce a novel notion of average signature $\mathbb{A}(G)$ valued in its tensor Lie algebra, by taking the average value of the signature of the unique length-minimizing geodesics between all pairs of generic points in $G$. we prove that using the average signature together with the trace operation with respect to the given bi-invariant Riemannian metric on $G$, one can recover certain geometric quantities of $G$, including the dimension, the diameter, the volume and the scalar curvature.

34 pages, final version, to appear in J. Lond. Math. Soc