Abstract
Real linear operators arise in a range of applications of mathematical physics. In this paper, basic properties of real linear operators are studied and their spectral theory is developed. Suitable extensions of classical operator theoretic concepts are introduced. Providing a concrete class, real linear multiplication operators are investigated and, motivated by the Beltrami equation, related problems of unitary approximation are addressed.
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Huhtanen, M., Ruotsalainen, S. Real Linear Operator Theory and its Applications. Integr. Equ. Oper. Theory 69, 113–132 (2011). https://doi.org/10.1007/s00020-010-1825-4
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DOI: https://doi.org/10.1007/s00020-010-1825-4