Some properties of the quartic numerical range for 4x4 operator matrices

Authors

Hakimboy Latipov, Bukhara State UniversityFollow

Abstract

In the present paper we consider self-adjoint 4x4 operator matrices A. For some special cases the alternative formulas for the calculating the quartic numerical range of 4x4 operator matrices A are derived. Using the obtained alternative formula for the quartic numerical range of A we estimate the lower and upper bound of A.

First Page

13

Last Page

20

References

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Recommended Citation

Latipov, Hakimboy (2023) "Some properties of the quartic numerical range for 4x4 operator matrices," Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences: Vol. 5: Iss. 1, Article 3.
DOI: https://doi.org/10.56017/2181-1318.1196