Dynamical functionals on ancient ARF Ricci flows
Isaac M. Lopez, Rio Schillmoeller
TL;DR
The paper develops a canonical dynamical energy framework for compact ancient ARF Ricci flows converging to a Ricci-flat metric and shows how a monotone dynamical functional, denoted $\\lambda_{\\mathrm{dyn}}^{\\infty}$, upper-bounds Perelman’s $\\lambda$-functional and enforces breather-type rigidity. It then extends Colding–Minicozzi style eigenvalue estimates to a drift Laplacian associated with a Ricci flow coupled to a conjugate heat flow, proving sharp local bounds for the first eigenvalue. Central to the construction are uniform a priori bounds for backward conjugate heat flows, leading to a limiting function $f^{\\infty}$ that defines the dynamical functional and underpins monotonicity and rigidity conclusions. Together, these results advance dynamical stability analysis of Ricci-flat metrics by bridging dynamical entropy-type functionals with local spectral control in ARF settings.
Abstract
We introduce a dynamical energy functional on compact ancient asymptotically Ricci-flat Ricci flows with modest decay using limits of conjugate heat flows. This functional satisfies a steady Ricci breather-type rigidity and provides an upper bound for the ordinary $λ$-functional while retaining many of its properties. In addition, motivated by work of Colding and Minicozzi, we derive local eigenvalue estimates for normalized Ricci flows coupled with conjugate heat flows.
