Ge, HuabinShi, Yipeng2016-07-252016-07-252016-06http://dx.doi.org/10.4236/apm.2016.67038http://hdl.handle.net/123456789/889In this paper, we consider L∞ estimates of eigenfunction, or more generally, the L∞ estimates of equation -Δu=fu. We use heat flow to give a new proof of the L∞ estimates for such type equations.enL∞ EstimatesEigenfunctionHeat FlowArticle