On the Uniform Boundedness of a Class of Hypersingular Integral Operators on the Hardy Space
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Abstract
For a class of hypersingular integral operators, we establish optimal uniform bounds for their norms on the Hardy space $H^1(\R)$. Our results extend the classical result of Fefferman-Stein for the phase function $1/y$ to phase functions of the form $1/P(y)$ where $P$ is an arbitrary real polynomial. It is revealed that the presence and absence of a constant term in $P$ play a crucial role in the outcome.
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