Lixin Yan

  1. Restriction estimates, sharp spectral multipliers and endpoint estimates for Bochner-Riesz means.

    Authors: Adam Sikora, Lixin Yan, Peng Chen, El Maati Ouhabaz
    Subjects: Analysis of PDEs
    Abstract

    We consider abstract non-negative self-adjoint operators on $L^2(X)$ which
    satisfy the finite speed propagation property for the corresponding wave
    equation. For such operators we introduce a restriction type condition which in
    the case of the standard Laplace operator is equivalent to $(p,2)$ restriction
    estimate of Stein and Tomas. Next we show that in the considered abstract
    setting our restriction type condition implies sharp spectral multipliers and
    endpoint estimates for the Bochner-Riesz summability.

  2. Weighted norm inequalities, Gaussian bounds and sharp spectral multipliers.

    Authors: Adam Sikora, Xuan Thinh Duong, Lixin Yan
    Subjects: Functional Analysis
    Abstract

    Let $L$ be a non-negative self adjoint operator acting on $L^2(X)$ where $X$
    is a space of homogeneous type. Assume that $L$ generates a holomorphic
    semigroup $e^{-tL}$ whose kernels $p_t(x,y)$ have Gaussian upper bounds but
    possess no regularity in variables $x$ and $y$. In this article, we study
    weighted $L^p$-norm inequalities for spectral multipliers of $L$. We show sharp
    weighted H\"ormander-type spectral multiplier theorems follow from Gaussian
    heat kernel bounds and appropriate $L^2$ estimates of the kernels of the
    spectral multipliers.

Syndicate content