[For the entire collection see Zbl 0699.00032.] A connection structure (M,H) and a path structure (M,S) on the manifold M are called compatible, if locally where and express the semi-spray S and the connection map H, resp. In the linear case of H its geodesic spray S is quadratic: On the contrary, the homogeneity condition of S induces the relation for the compatible connection H, whence it follows not that H is linear, i.e. if a connection structure is compatible with a spray, then the connection is not necessarily homogeneous. This fact supplements the investigations of H. B. Levine [Phys. Fluids 3, 225-245 (1960; Zbl 0106.209)], and M. Crampin [J. Lond. Math. Soc., II. Ser. 3, 178-182 (1971; Zbl 0215.510)].
@article{701466, title = {On sprays and connections}, booktitle = {Proceedings of the Winter School "Geometry and Physics"}, series = {GDML\_Books}, publisher = {Circolo Matematico di Palermo}, address = {Palermo}, year = {1990}, pages = {[113]-116}, mrnumber = {MR1061793}, zbl = {0707.53025}, url = {http://dml.mathdoc.fr/item/701466} }
Kozma, László. On sprays and connections, dans Proceedings of the Winter School "Geometry and Physics", GDML_Books, (1990), pp. [113]-116. http://gdmltest.u-ga.fr/item/701466/