# A NOTE ON FOCAL POINT COMPARISON IN RIEMANNIAN GEOMETRY

• Kim, Jong-Ryul (Department of Mathematics, Kunsan National University)
• Accepted : 2012.05.10
• Published : 2012.06.25

#### Abstract

Using a comparison of the Jacobi differential equations instead of volume comparison by Itokawa in [3], the focal radius is estimated under the suitable Ricci and mean curvature conditions.

#### Acknowledgement

Supported by : Kunsan National University

#### References

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