Abstract.
Simple facts about the Poincaré-Neumann double layer potential are used in the construction of a normal dilation, on the numerical range of an arbitrary Hilbert space operator. Recent and old ideas in the theory of the numerical range are unified by this framework. A couple of mapping results for the numerical range are derived.
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Revised version: 15 July 2002
First author partially supported by the National Science Foundation Grant DMS 0100367, Second author supported by STINT, The Swedish Foundation for International Cooperation in Research and Higher Education.
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Putinar, M., Sandberg, S. A skew normal dilation on the numerical range of an operator. Math. Ann. 331, 345–357 (2005). https://doi.org/10.1007/s00208-004-0585-3
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DOI: https://doi.org/10.1007/s00208-004-0585-3