## Symbolic computation applied to the study of the kernel of special classes of paired singular integral operators.(English)Zbl 1491.68275

Summary: Operator theory has many applications in several main scientific research areas (structural mechanics, aeronautics, quantum mechanics, ecology, probability theory, electrical engineering, among others) and the importance of its study is globally acknowledged. On the study of the operator’s kernel some progress has been achieved for some specific classes of singular integral operators whose properties allow the use of particular strategies. However, the existing algorithms allow, in general, to study the dimension of the kernel of some classes of singular integral operators but are not designed to be implemented on a computer. The main goal of this paper is to show how the symbolic and numeric capabilities of a computer algebra system can be used to study the kernel of special classes of paired singular integral operators with essentially bounded coefficients defined on the unit circle. It is described how some factorization algorithms can be used to compute the dimension of the kernel of special classes of singular integral operators. The analytical algorithms [ADimKerPaired-Scalar], [AKerPaired-Scalar], and [ADimKerPaired-Matrix] are presented. The design of these new algorithms was focused on the possibility of implementing on a computer all the extensive symbolic and numeric calculations present in the algorithms. For the essentially bounded hermitian coefficients case, there exist some relations with Hankel operators. The paper contains some interesting and nontrivial examples obtained with the use of a computer algebra system.

### MSC:

 68W30 Symbolic computation and algebraic computation 30E20 Integration, integrals of Cauchy type, integral representations of analytic functions in the complex plane 47A68 Factorization theory (including Wiener-Hopf and spectral factorizations) of linear operators 47B35 Toeplitz operators, Hankel operators, Wiener-Hopf operators 47G10 Integral operators

### Software:

Mathematica; ASpecPaired-Matrix; SInt; ASpecPaired-Scalar
Full Text:

### References:

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