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Almost everywhere convergence of spectral sums for self-adjoint operators

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 نشر من قبل Peng Chen
 تاريخ النشر 2021
  مجال البحث
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Let $L$ be a non-negative self-adjoint operator acting on the space $L^2(X)$, where $X$ is a metric measure space. Let ${ L}=int_0^{infty} lambda dE_{ L}({lambda})$ be the spectral resolution of ${ L}$ and $S_R({ L})f=int_0^R dE_{ L}(lambda) f$ denote the spherical partial sums in terms of the resolution of ${ L}$. In this article we give a sufficient condition on $L$ such that $$ lim_{Rrightarrow infty} S_R({ L})f(x) =f(x), {rm a.e.} $$ for any $f$ such that ${rm log } (2+L) fin L^2(X)$. These results are applicable to large classes of operators including Dirichlet operators on smooth bounded domains, the Hermite operator and Schrodinger operators with inverse square potentials.



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