참고문헌
- Einstein manifolds A.L. Besse
- Einstein-Thorpe Manifolds J.M.Kim
- Annals of Mathematics v.80 Sectional curvatures and characteristic classes J.A. Thorpe
- Journal of Mathematics and Mechanics v.18 Some remarks on the Gauss-Bonnet integral
On Riemannian manifolds of dimension 4 the Einstein condition is equivalent to the Thorpe condition. In this paper, we construct a few metrics which we Einstein but not Thorpe, and vice versa in dimensions larger than 4.