The Second Variation of the Ricci Expander Entropy
نویسنده
چکیده
In [10], Perelman discovered two important functionals, the F -functional and the W functional. The corresponding entropy functionals λ and ν are monotone along the Ricci flow ∂gij ∂t = −2Rij and constant precisely on steady and shrinking solitons. In [2], H.-D. Cao, R. Hamilton and T. Ilmanen presented the second variations of both entropy functionals and studied the linear stabilities of certain closed Einstein manifolds of nonnegative scalar curvature.
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تاریخ انتشار 2009