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The totality of the eigenvalues of the Laplacian of a compact Riemannian manifold is called the spectrum. We describe how the spectrum determines a Riemannian manifold. The continuity of the eigenvalue of the Laplacian, Cheeger and Yau's estimate of the first eigenvalue, the Lichnerowicz–Obata's theorem on the first eigenvalue, the Cheng's estimates of the k th eigenvalues, and Payne–Pólya–Weinberger's inequality of the Dirichlet eigenvalue of the Laplacian are also described. Then, the theorem of Colin de Verdière, that is, the spectrum determines the totality of all the lengths of closed geodesics is described. We give the V Guillemin and D Kazhdan's theorem which determines the Riemannian manifold of negative curvature.
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Contents:
- Fundamental Materials of Riemannian Geometry
- The Space of Riemannian Metrics, and Continuity of the Eigenvalues
- Cheeger and Yau Estimates on the Minimum Positive Eigenvalue
- The Estimations of the k th Eigenvalue and Lichnerowicz-Obata's Theorem
- The Payne, Pólya and Weinberger Type Inequalities for the Dirichlet Eigenvalues
- The Heat Equation and the Set of Lengths of Closed Geodesics
- Negative Curvature Manifolds and the Spectral Rigidity Theorem
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Readership: Researchers in differential geometry and partial differential equations.
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