A homogeneous Riemannian manifold is called a “g.o. space” if every geodesic on arises as an orbit of a one-parameter subgroup of . Let be such a “g.o. space”, and an -invariant vector subspace of such that . A geodesic graph is a map such that is a geodesic for every . The author calculates explicitly such geodesic graphs for certain special 2-step nilpotent Lie groups. More precisely, he deals with “generalized Heisenberg groups” (also known as “H-type groups”) whose center has dimension not exceeding three.
@article{701689, title = {Explicit geodesic graphs on some H-type groups}, booktitle = {Proceedings of the 21st Winter School "Geometry and Physics"}, series = {GDML\_Books}, publisher = {Circolo Matematico di Palermo}, address = {Palermo}, year = {2002}, pages = {[77]-88}, mrnumber = {MR1972426}, zbl = {1025.53019}, url = {http://dml.mathdoc.fr/item/701689} }
Dušek, Zdeněk. Explicit geodesic graphs on some H-type groups, dans Proceedings of the 21st Winter School "Geometry and Physics", GDML_Books, (2002), pp. [77]-88. http://gdmltest.u-ga.fr/item/701689/