The First Positive Eigenvalue of the Sub-laplacian on Cr Spheres
نویسندگان
چکیده
We prove that the first positive eigenvalue, normalized by the volume, of the sub-Laplacian associated with a strictly pseudoconvex pseudo-Hermitian structure θ on the CR sphere S ⊂ C, achieves its maximum when θ is the standard contact form.
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