## Smoothness of the metric of spaces with two-sided bounded Aleksandrov curvature.(English. Russian original)Zbl 0547.53011

Sib. Math. J. 24, 247-263 (1983); translation from Sib. Mat. Zh. 24, No. 2(138), 114-132 (1983).
Let M be a space with two-sided bounded curvature in the sense of A. D. Aleksandrov. The author proves that the components $$g_{ij}$$ of the metric tensor with respect to a certain coordinate system constructed by V. N. Berestovskij [Sib. Mat. Zh. 16, 651-662 (1975; Zbl 0325.53059)] are locally Lipschitz and that in the neighborhood of any point of M one can introduce harmonic coordinates. Complete proofs of some results [Theorem 1,c) and Theorem 2] previously announced [Dokl. Akad. Nauk SSSR 250, 1056-1058 (1980; Zbl 0505.53015)] are also given. In particular, if $$\Omega$$ is the domain of a system of harmonic coordinates, then with respect to such a system $$g_{ij}$$ has second order differentials in the classical sense almost everywhere on $$\Omega$$.
Reviewer: M.Craioveanu

### MSC:

 53B20 Local Riemannian geometry

### Citations:

Zbl 0325.53059; Zbl 0505.53015
Full Text:

### References:

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