6th Summer Workshop on Operator Theory

9th - 13th July 2018 Kraków

Eungil Ko

On square roots of self-adjoint weighted composition operators on H2

In this talk, we characterize square roots of self-adjoint weighted composition operators on the Hardy space H2, i.e., Wg, ψ such that Wg, ψ =Wf, Φ2 is self-adjoint. In particular, we find symbol functions f and Φ in this case. Some of Wf, Φ may be other, nonself-adjoint weighted composition operators. We also investigate several properties of such Wf, Φ. Finally, we give equivalent conditions for such Wf, Φ to be self-adjoint or normal, respectively.

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This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2016R1D1A1B03931937).

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