Li-Yau gradient estimate and entropy formulae for the CR heat equation in a closed pseudohermitian 3-manifold
A CR manifold with a fixed contact form is called a pseudohermitian manifold; see [\textit{J. M. Lee}, Am. J. Math. 110, No. 1, 157--178 (1988; Zbl 0638.32019)].NEWLINENEWLINE\textit{H.-D. Cao} and \textit{S.-T. Yau} [Math. Z. 211, No. 3, 485--504 (1992; Zbl 0808.58037)] introduced a CR analogue of the heat flow on a pseudohermitian 3-manifold. In the present paper the authors derive subgradient estimates analogous to the Li-Yau gradient estimate and a Perelman-type entropy formula for this CR heat flow.
scientific article; zbMATH DE number 6050958