On the CR–Obata theorem and some extremal problems associated to pseudo scalar curvature on the real ellipsoids in C
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چکیده
where (hαβ) is the positive definite n × n matrix on M , which is uniquely determined by the Levi form Lθ(u, v) = −idθ(u, v) for u, v ∈ H(M). Let ∆sb be the sub-Laplacian with respect to θ (see [8], [22] and [7] for references) and let μ1 be the first positive eigenvalue of ∆sb on (M, θ). Let Rαβ be the Webster pseudo Ricci curvature, R be the pseudo scalar curvature and Tor be the pseudo torsion defined in [26]. Under the condition:
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تاریخ انتشار 2009