2020/07/03 by Zhijie Fan, Fan, Zhijie
Mathematics · #Advanced Harmonic Analysis Research #Advanced Mathematical Physics Problems #Analysis of PDEs (math.AP) #FOS: Mathematics #Nonlinear Partial Differential Equations
paper · pdf · doi:10.48550/arxiv.2007.01468
openalex publication_date 2020/07/03 · openalex created_date 2020/07/10 · openalex updated_date 2026/07/28
Let L be a non-negative self-adjoint operator acting on L2(X), where X is a space of homogeneous type with a dimension n. Suppose that the heat operator e-tL satisfies the generalized Gaussian (p0, p'0)-estimates of order m for some 1≤ p0 < 2. It is known that the operator (I+L)-s eitL is bounded on Lp(X) for s≥ n|1/ 2-1/p| and p∈ (p0, p0') (see for example, \citeBlunck2, BDN, CCO, CDLY, DN, Mi1). In this paper we study the endpoint case p=p0 and show that for s0= n|1\over 2-1\over p0|, the operator (I+L)^-s0eitL is of weak type (p0,p0), that is, there is a constant C>0, independent of t and f so that μ(\x: |(I+L)-s0eitL f(x)|gt;α\ )≤ C (1+|t|)^n(1 - p0\over 2) ( ‖f‖p0 \over α )p0 , t∈\mathbb R for α>0 when μ(X)=∞, and α>(‖f‖_p0/μ(X) )^p0 when μ(X)